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Sample records for multiple cross-layer design

  1. The Balanced Cross-Layer Design Routing Algorithm in Wireless Sensor Networks Using Fuzzy Logic

    PubMed Central

    Li, Ning; Martínez, José-Fernán; Díaz, Vicente Hernández

    2015-01-01

    Recently, the cross-layer design for the wireless sensor network communication protocol has become more and more important and popular. Considering the disadvantages of the traditional cross-layer routing algorithms, in this paper we propose a new fuzzy logic-based routing algorithm, named the Balanced Cross-layer Fuzzy Logic (BCFL) routing algorithm. In BCFL, we use the cross-layer parameters’ dispersion as the fuzzy logic inference system inputs. Moreover, we give each cross-layer parameter a dynamic weight according the value of the dispersion. For getting a balanced solution, the parameter whose dispersion is large will have small weight, and vice versa. In order to compare it with the traditional cross-layer routing algorithms, BCFL is evaluated through extensive simulations. The simulation results show that the new routing algorithm can handle the multiple constraints without increasing the complexity of the algorithm and can achieve the most balanced performance on selecting the next hop relay node. Moreover, the Balanced Cross-layer Fuzzy Logic routing algorithm can adapt to the dynamic changing of the network conditions and topology effectively. PMID:26266412

  2. The Balanced Cross-Layer Design Routing Algorithm in Wireless Sensor Networks Using Fuzzy Logic.

    PubMed

    Li, Ning; Martínez, José-Fernán; Hernández Díaz, Vicente

    2015-08-10

    Recently, the cross-layer design for the wireless sensor network communication protocol has become more and more important and popular. Considering the disadvantages of the traditional cross-layer routing algorithms, in this paper we propose a new fuzzy logic-based routing algorithm, named the Balanced Cross-layer Fuzzy Logic (BCFL) routing algorithm. In BCFL, we use the cross-layer parameters' dispersion as the fuzzy logic inference system inputs. Moreover, we give each cross-layer parameter a dynamic weight according the value of the dispersion. For getting a balanced solution, the parameter whose dispersion is large will have small weight, and vice versa. In order to compare it with the traditional cross-layer routing algorithms, BCFL is evaluated through extensive simulations. The simulation results show that the new routing algorithm can handle the multiple constraints without increasing the complexity of the algorithm and can achieve the most balanced performance on selecting the next hop relay node. Moreover, the Balanced Cross-layer Fuzzy Logic routing algorithm can adapt to the dynamic changing of the network conditions and topology effectively.

  3. A novel cross-layer protocol design for planetary satellite network systems

    NASA Astrophysics Data System (ADS)

    Li, Lixin; Dai, Guanzhong; Zhang, Zhi; Zhao, Yuting; Xu, Hao; Yang, Deming

    2005-11-01

    The Planetary Satellite Network consists of the satellites orbiting the planets to provide communication relay and navigation services to the surface elements, which are often spread out to form an Ad hoc network. However, the current TCP/IP layered protocols have very poor performance in the Planetary Satellite Network, which is characterized by extremely high propagation delays, link errors, asymmetrical bandwidth and blackouts. In this paper, a novel cross-layer protocol design that supports adaptability and optimization across multiple layers of the protocol stack is presented to solve the performance problem of the Planetary Satellite Network. This cross-layer feedback design on a Planetary Satellite device aims to optimize overall network performance by increasing local interaction among protocols, decreasing remote communications, and consequently saving network bandwidth, improving the QoS performance.

  4. Cross-Layer Design and Optimization for Wireless Sensor Networks

    DTIC Science & Technology

    2006-03-01

    A survey on sensor networks,” IEEE Communications Magazine , Vol. 40, No. 8, pp. 102-116, Aug 2002. [5] Sameer Tilak, Nael B. Abu-Ghazaleh...2004. [9] Jeyhan Karagoux, “High-Rate Wireless Personal Area Networks,” IEEE Communications Magazine ,” Vol.39 No.12, pp. 96-102, Dec. 2001. [10...rate adaptation and energy-saving mechanisms based on cross-layer information for packet-switched data networks", IEEE Communications Magazine , Vol

  5. Cross-layer Design for MIMO Systems with Transmit Antenna Selection and Imperfect CSI

    NASA Astrophysics Data System (ADS)

    Yu, Xiangbin; Liu, Yan; Rui, Yun; Zhou, Tingting; Yin, Xin

    2013-04-01

    In this paper, by combining adaptive modulation and automatic repeat request (ARQ), a cross-layer design (CLD) scheme for multiple-input and multiple-output (MIMO) system with transmit antenna selection (TAS) and imperfect channel state information (CSI) is presented. Based on the imperfect CSI, the probability density function of the effective signal to noise ratio (SNR) is derived, and the fading gain switching thresholds are also derived subject to a target packet loss rate and fixed power constraint. According to these results, we further derive the average spectrum efficiency (SE) and packet error rate (PER) of the system. As a result, closed-form expressions of the average SE and PER are obtained, respectively. The derived expressions include the expressions under perfect CSI as special cases, and can provide good performance evaluation for the CLD system with imperfect CSI. Simulation results verify the validity of the theoretical analysis. The results show that the CLD system with TAS provides better SE than that with space-time block coding, but the SE and PER performance of the system with imperfect CSI are worse than those with perfect CSI due to the estimation error.

  6. Collision avoidance in TV white spaces: a cross-layer design approach for cognitive radio networks

    NASA Astrophysics Data System (ADS)

    Foukalas, Fotis; Karetsos, George T.

    2015-07-01

    One of the most promising applications of cognitive radio networks (CRNs) is the efficient exploitation of TV white spaces (TVWSs) for enhancing the performance of wireless networks. In this paper, we propose a cross-layer design (CLD) of carrier sense multiple access with collision avoidance (CSMA/CA) mechanism at the medium access control (MAC) layer with spectrum sensing (SpSe) at the physical layer, for identifying the occupancy status of TV bands. The proposed CLD relies on a Markov chain model with a state pair containing both the SpSe and the CSMA/CA from which we derive the collision probability and the achievable throughput. Analytical and simulation results are obtained for different collision avoidance and SpSe implementation scenarios by varying the contention window, back off stage and probability of detection. The obtained results depict the achievable throughput under different collision avoidance and SpSe implementation scenarios indicating thereby the performance of collision avoidance in TVWSs-based CRNs.

  7. Q-learning-based cross-layer Learning Engine design for cognitive radio network

    NASA Astrophysics Data System (ADS)

    Liu, Congbin; Jiang, Hong; Yang, Yanchao; Ma, Jinghui

    2013-03-01

    In cognitive radio (CR) networks, Learning Engine has considerable significance on dynamic spectrum access (DSA) and implementation of cognitive function. In this paper, a cross-layer learning engine design scheme is proposed by jointly considering physical-layer dynamic channel selection, modulation and coding scheme, data-link layer frame length in CR networks, with the purpose to maximize system throughput and simultaneously meet heterogeneous Quality of Service (QoS) requirements. The wireless fading channel is modeled as a continuous state space Markov decision process (MDP) and the licensed network activity is abstracted as a finite-state one. We introduce Q-learning algorithm to realize the function of learning from state space and adapt wireless environment. And meanwhile a large scale Qfunction approximator based on support vector machine (SVM) is employed to effectively reduce storage requirement and decrease the operation complexity. A cross-layer learning engine communication platform is realized by using Matlab simulator. the simulation results demonstrate that while lacking system prior knowledge, the learning engine can effectively achieve configuration function by system cross-layer learning approach, and furthermore, it can converge to the best—i.e., realize reconfiguration function in CR networks while meeting users' QoS.

  8. Cross Layer Design for Optimizing Transmission Reliability, Energy Efficiency, and Lifetime in Body Sensor Networks

    PubMed Central

    Chen, Xi; Xu, Yixuan; Liu, Anfeng

    2017-01-01

    High transmission reliability, energy efficiency, and long lifetime are pivotal issues for wireless body area networks (WBANs). However, these performance metrics are not independent of each other, making it hard to obtain overall improvements through optimizing one single aspect. Therefore, a Cross Layer Design Optimal (CLDO) scheme is proposed to simultaneously optimize transmission reliability, energy efficiency, and lifetime of WBANs from several layers. Firstly, due to the fact that the transmission power of nodes directly influences the reliability of links, the optimized transmission power of different nodes is deduced, which is able to maximize energy efficiency in theory under the premise that requirements on delay and jitter are fulfilled. Secondly, a relay decision algorithm is proposed to choose optimized relay nodes. Using this algorithm, nodes will choose relay nodes that ensure a balance of network energy consumption, provided that all nodes transmit with optimized transmission power and the same packet size. Thirdly, the energy consumption of nodes is still unbalanced even with optimized transmission power because of their different locations in the topology of the network. In addition, packet size also has an impact on final performance metrics. Therefore, a synthesized cross layer method for optimization is proposed. With this method, the transmission power of nodes with more residual energy will be enhanced while suitable packet size is determined for different links in the network, leading to further improvements in the WBAN system. Both our comprehensive theoretical analysis and experimental results indicate that the performance of our proposed scheme is better than reported in previous studies. Relative to the relay selection and power control game (RSPCG) scheme, the CLDO scheme can enhance transmission reliability by more than 44.6% and prolong the lifetime by as much as 33.2%. PMID:28422062

  9. Cross Layer Design for Optimizing Transmission Reliability, Energy Efficiency, and Lifetime in Body Sensor Networks.

    PubMed

    Chen, Xi; Xu, Yixuan; Liu, Anfeng

    2017-04-19

    High transmission reliability, energy efficiency, and long lifetime are pivotal issues for wireless body area networks (WBANs. However, these performance metrics are not independent of each other, making it hard to obtain overall improvements through optimizing one single aspect. Therefore, a Cross Layer Design Optimal (CLDO) scheme is proposed to simultaneously optimize transmission reliability, energy efficiency, and lifetime of WBANs from several layers. Firstly, due to the fact that the transmission power of nodes directly influences the reliability of links, the optimized transmission power of different nodes is deduced, which is able to maximize energy efficiency in theory under the premise that requirements on delay and jitter are fulfilled. Secondly, a relay decision algorithm is proposed to choose optimized relay nodes. Using this algorithm, nodes will choose relay nodes that ensure a balance of network energy consumption, provided that all nodes transmit with optimized transmission power and the same packet size. Thirdly, the energy consumption of nodes is still unbalanced even with optimized transmission power because of their different locations in the topology of the network. In addition, packet size also has an impact on final performance metrics. Therefore, a synthesized cross layer method for optimization is proposed. With this method, the transmission power of nodes with more residual energy will be enhanced while suitable packet size is determined for different links in the network, leading to further improvements in the WBAN system. Both our comprehensive theoretical analysis and experimental results indicate that the performance of our proposed scheme is better than reported in previous studies. Relative to the relay selection and power control game (RSPCG) scheme, the CLDO scheme can enhance transmission reliability by more than 44.6% and prolong the lifetime by as much as 33.2%.

  10. Robust System and Cross-Layer Design for H.264/AVC-Based Wireless Video Applications

    NASA Astrophysics Data System (ADS)

    Stockhammer, Thomas

    2006-12-01

    H.264/AVC is an essential component in emerging wireless video applications, thanks to its excellent compression efficiency and network-friendly design. However, a video coding standard itself is only a single component within a complex system. Its effectiveness strongly depends on the appropriate configuration of encoders, decoders, as well as transport and network features. The applicability of different features depends on application constraints, the availability and quality of feedback and cross-layer information, and the accessible quality-of-service (QoS) tools in modern wireless networks. We discuss robust integration of H.264/AVC in wireless real-time video applications. Specifically, the use of different coding and transport-related features for different application types is elaborated. Guidelines for the selection of appropriate coding tools, encoder and decoder settings, as well as transport and network parameters are provided and justified. Selected simulation results show the superiority of lower layer error control over application layer error control and video error resilience features.

  11. Optimal Policy of Cross-Layer Design for Channel Access and Transmission Rate Adaptation in Cognitive Radio Networks

    NASA Astrophysics Data System (ADS)

    He, Hao; Wang, Jun; Zhu, Jiang; Li, Shaoqian

    2010-12-01

    In this paper, we investigate the cross-layer design of joint channel access and transmission rate adaptation in CR networks with multiple channels for both centralized and decentralized cases. Our target is to maximize the throughput of CR network under transmission power constraint by taking spectrum sensing errors into account. In centralized case, this problem is formulated as a special constrained Markov decision process (CMDP), which can be solved by standard linear programming (LP) method. As the complexity of finding the optimal policy by LP increases exponentially with the size of action space and state space, we further apply action set reduction and state aggregation to reduce the complexity without loss of optimality. Meanwhile, for the convenience of implementation, we also consider the pure policy design and analyze the corresponding characteristics. In decentralized case, where only local information is available and there is no coordination among the CR users, we prove the existence of the constrained Nash equilibrium and obtain the optimal decentralized policy. Finally, in the case that the traffic load parameters of the licensed users are unknown for the CR users, we propose two methods to estimate the parameters for two different cases. Numerical results validate the theoretic analysis.

  12. Ambient Intelligence Context-Based Cross-Layer Design in Wireless Sensor Networks

    PubMed Central

    Liu, Yang; Seet, Boon-Chong; Al-Anbuky, Adnan

    2014-01-01

    By exchanging information directly between non-adjacent protocol layers, cross-layer (CL) interaction can significantly improve and optimize network performances such as energy efficiency and delay. This is particularly important for wireless sensor networks (WSNs) where sensor devices are energy-constrained and deployed for real-time monitoring applications. Existing CL schemes mainly exploit information exchange between physical, medium access control (MAC), and routing layers, with only a handful involving application layer. For the first time, we proposed a framework for CL optimization based on user context of ambient intelligence (AmI) application and an ontology-based context modeling and reasoning mechanism. We applied the proposed framework to jointly optimize MAC and network (NET) layer protocols for WSNs. Extensive evaluations show that the resulting optimization through context awareness and CL interaction for both MAC and NET layer protocols can yield substantial improvements in terms of throughput, packet delivery, delay, and energy performances. PMID:25317760

  13. Cross-layer Design of Wireless Networks with Resource-Constrained Nodes

    DTIC Science & Technology

    2004-06-02

    RR bpsR APPROVED FOR PUBLIC RELEASE Cooperative MIMO Nodes close together can cooperatively transmit Form a multiple -antenna transmitter ( MIMO ...Broadcast) Nodes close together can cooperatively receive Form a multiple -antenna receiver ( MIMO MAC) MIMO introduces capacity vs. diversity tradeoffs...Adding power control (e): Successive interference cancellation, no power control. jiijRij ≠≠= ,34,12 ,0 Multiple hops Spatial reuse

  14. Cross-Layer Design Approach for Wireless Networks to Improve the Performance POSTPRINT)

    DTIC Science & Technology

    2010-06-01

    licensed use limited to: AFRL Technical Library. Downloaded on June 24,2010 at 14:11:27 UTC from IEEE Xplore . Restrictions apply. 1 A recent design...Library. Downloaded on June 24,2010 at 14:11:27 UTC from IEEE Xplore . Restrictions apply. 2 We will outline some of the challenges that the designers...limited to: AFRL Technical Library. Downloaded on June 24,2010 at 14:11:27 UTC from IEEE Xplore . Restrictions apply. 3 back-and-forth design

  15. Cross-Layer Design for Downlink Multihop Cloud Radio Access Networks With Network Coding

    NASA Astrophysics Data System (ADS)

    Liu, Liang; Yu, Wei

    2017-04-01

    There are two fundamentally different fronthaul techniques in the downlink communication of cloud radio access network (C-RAN): the data-sharing strategy and the compression-based strategy. Under the former strategy, each user's message is multicast from the central processor (CP) to all the serving remote radio heads (RRHs) over the fronthaul network, which then cooperatively serve the users through joint beamforming; while under the latter strategy, the user messages are first beamformed then quantized at the CP, and the compressed signal is unicast to the corresponding RRH, which then decompresses its received signal for wireless transmission. Previous works show that in general the compression-based strategy outperforms the data-sharing strategy. This paper, on the other hand, point s out that in a C-RAN model where the RRHs are connected to the CP via multi-hop routers, data-sharing can be superior to compression if the network coding technique is adopted for multicasting user messages to the cooperating RRHs, and the RRH's beamforming vectors, the user-RRH association, and the network coding design over the fronthaul network are jointly optimized based on the techniques of sparse optimization an d successive convex approximation. This is in comparison to the compression-based strategy, where information is unicast over the fronthaul network by simple routing, and the RRH's compression noise covariance and beamforming vectors, as well as the routing strategy over the fronthaul network are jointly optimized based on the successive convex approximation technique. The observed gain in overall network throughput is due to that information multicast is more efficient than information unicast over the multi-hop fronthaul of a C-RAN.

  16. A Review of Protocol Implementations and Energy Efficient Cross-Layer Design for Wireless Body Area Networks

    PubMed Central

    Hughes, Laurie; Wang, Xinheng; Chen, Tao

    2012-01-01

    The issues inherent in caring for an ever-increasing aged population has been the subject of endless debate and continues to be a hot topic for political discussion. The use of hospital-based facilities for the monitoring of chronic physiological conditions is expensive and ties up key healthcare professionals. The introduction of wireless sensor devices as part of a Wireless Body Area Network (WBAN) integrated within an overall eHealth solution could bring a step change in the remote management of patient healthcare. Sensor devices small enough to be placed either inside or on the human body can form a vital part of an overall health monitoring network. An effectively designed energy efficient WBAN should have a minimal impact on the mobility and lifestyle of the patient. WBAN technology can be deployed within a hospital, care home environment or in the patient's own home. This study is a review of the existing research in the area of WBAN technology and in particular protocol adaptation and energy efficient cross-layer design. The research reviews the work carried out across various layers of the protocol stack and highlights how the latest research proposes to resolve the various challenges inherent in remote continual healthcare monitoring. PMID:23202185

  17. Cross layer design for optimised region of interest of ultrasound video data over mobile WiMAX.

    PubMed

    Debono, Carl J; Micallef, Brian W; Philip, Nada Y; Alinejad, Ali; Istepanian, Robert S H; Amso, Nazar N

    2012-11-01

    The application of advanced error concealment techniques applied as a post-process to conceal lost video information in error-prone channels, such as the wireless channel, demand additional processing at the receiver. This increases the delivery delay and needs more computational power. However, in general, only a small region within medical video is of interest to the physician and thus if only this area is considered, the number of computations can be curtailed. In this paper we present a technique whereby the Region of Interest (ROI) specified by the physician is used to delimit the area where the more complex concealment techniques are applied. A cross layer design approach in mobile WiMAX wireless communication environment is adopted in this paper to provide an optimized Quality of Experience (QoE) in the region that matters most to the mobile physician while relaxing the requirements in the background, ensuring real-time delivery. Results show that a diagnostically acceptable Peak Signal-to-Noise-Ratio (PSNR) of about 36 dB can still be achieved within reasonable decoding time.

  18. Mobility Prediction Progressive Routing (MP2R), a Cross-Layer Design for Inter-Vehicle Communication

    NASA Astrophysics Data System (ADS)

    Tang, Suhua; Kadowaki, Naoto; Obana, Sadao

    In this paper we analyze the characteristics of vehicle mobility and propose a novel Mobility Prediction Progressive Routing (MP2R) protocol for Inter-Vehicle Communication (IVC) that is based on crosslayer design. MP2R utilizes the additional gain provided by the directional antennas to improve link quality and connectivity; interference is reduced by the directional transmission. Each node learns its own position and speed and that of other nodes, and performs position prediction. (i) With the predicted progress and link quality, the forwarding decision of a packet is locally made, just before the packet is actually transmitted. In addition the load at the forwarder is considered in order to avoid congestion. (ii) The predicted geographic direction is used to control the beam of the directional antenna. The proposed MP2R protocol is especially suitable for forwarding burst traffic in highly mobile environments. Simulation results show that MP2R effectively reduces Packet Error Ratio (PER) compared with both topology-based routing (AODV [1], FSR [2]) and normal progressive routing (NADV [18]) in the IVC scenarios.

  19. An Improved Cross-Layering Design for IPv6 Fast Handover with IEEE 802.16m Entry Before Break Handover

    NASA Astrophysics Data System (ADS)

    Kim, Ronny Yongho; Jung, Inuk; Kim, Young Yong

    IEEE 802.16m is an advanced air interface standard which is under development for IMT-Advanced systems, known as 4G systems. IEEE 802.16m is designed to provide a high data rate and a Quality of Service (QoS) level in order to meet user service requirements, and is especially suitable for mobilized environments. There are several factors that have great impact on such requirements. As one of the major factors, we mainly focus on latency issues. In IEEE 802.16m, an enhanced layer 2 handover scheme, described as Entry Before Break (EBB) was proposed and adopted to reduce handover latency. EBB provides significant handover interruption time reduction with respect to the legacy IEEE 802.16 handover scheme. Fast handovers for mobile IPv6 (FMIPv6) was standardized by Internet Engineering Task Force (IETF) in order to provide reduced handover interruption time from IP layer perspective. Since FMIPv6 utilizes link layer triggers to reduce handover latency, it is very critical to jointly design FMIPv6 with its underlying link layer protocol. However, FMIPv6 based on new handover scheme, EBB has not been proposed. In this paper, we propose an improved cross-layering design for FMIPv6 based on the IEEE 802.16m EBB handover. In comparison with the conventional FMIPv6 based on the legacy IEEE 802.16 network, the overall handover interruption time can be significantly reduced by employing the proposed design. Benefits of this improvement on latency reduction for mobile user applications are thoroughly investigated with both numerical analysis and simulation on various IP applications.

  20. A Closed-loop Cross-Layer Scheme for Wireless Multiuser Transmissions

    NASA Astrophysics Data System (ADS)

    Guo, Lili; Wang, Yang

    To improve transmission efficiency of wireless communication systems, cross-layer design is investigated, which can adapt to the dynamically variable wireless channel characters. In this paper, a novel cross-layer design for multi-user system is proposed to improve system performance. The Beamforming-MIMO cross-layer system is scheduled through combining multilevel adaptive modulation (AM) at physical layer with truncated automatic repeat request (ARQ) protocol at data link layer, and feed backing modulation mode, ARQ request and transmit weight vector from receiver, in order to improve multi-antennas system performance. This paper derives close-form expressions of the system spectral efficiency and the outage probability for wireless multiuser MIMO transmissions. It shows by simulation that, compared to Alamouti's cross-layer system and SISO cross-layer system, this cross-layer system can achieve better performance. And we analyze the impact of the transmit antenna number and mobile user number on the performance.

  1. Wireless Visual Sensor Network Resource Allocation using Cross-Layer Optimization

    DTIC Science & Technology

    2009-01-01

    channel coding. 2. RESOURCE ALLOCATION USING CROSS - LAYER OPTIMIZATION This work considers a wireless visual sensor network that...SUBJECT TERMS Cross - layer , visual sensor network , Code Division Multiple Access (CDMA), resource allocation, H.265, spread spectrum, joint source- channel ...DATES COVERED (From - To) January 2008 – August 2008 4. TITLE AND SUBTITLE WIRELESS VISUAL SENSOR NETWORK RESOURCE ALLOCATION USING CROSS -

  2. Physical and Cross-Layer Security Enhancement and Resource Allocation for Wireless Networks

    ERIC Educational Resources Information Center

    Bashar, Muhammad Shafi Al

    2011-01-01

    In this dissertation, we present novel physical (PHY) and cross-layer design guidelines and resource adaptation algorithms to improve the security and user experience in the future wireless networks. Physical and cross-layer wireless security measures can provide stronger overall security with high efficiency and can also provide better…

  3. Physical and Cross-Layer Security Enhancement and Resource Allocation for Wireless Networks

    ERIC Educational Resources Information Center

    Bashar, Muhammad Shafi Al

    2011-01-01

    In this dissertation, we present novel physical (PHY) and cross-layer design guidelines and resource adaptation algorithms to improve the security and user experience in the future wireless networks. Physical and cross-layer wireless security measures can provide stronger overall security with high efficiency and can also provide better…

  4. Cross-layer Optimization for Next Generation Wi-Fi

    NASA Astrophysics Data System (ADS)

    Redieteab, Getachew

    2013-01-01

    From the initial 1997 specification to the undergoing IEEE 802.11ac standardization, a leap in throughput has been observed with every new generation. The expectations for next generations on issues like throughput, range, reliability, and power consumption are even higher. This is quite a challenge considering all the work already done. Cross-layer optimization of physical (PHY) and medium access control (MAC) layers can be an interesting exploration path for further enhancement. During this thesis we have studied cross-layer optimization techniques, with a focus on the IEEE 802.11ac standard. A new multichannel aggregation scheme involving cross-knowledge between PHY and MAC layers has been proposed to improve performance in collision-prone environments. We have shown that some functionalities directly involved PHY and MAC layers. An accurate modeling of both PHY and MAC mechanisms is thus needed to have a realistic characterization of such functionalities. A cross-layer simulator, compliant with IEEE 802.11ac specifications, has thus been implemented. To the best of our knowledge, this is the first simulator incorporating detailed PHY and MAC functionalities for the IEEE 802.11ac standard. The multiple-user multiple-input, multiple-output (MU-MIMO) technique, which is one of the main innovations of the IEEE 802.11ac, needs both PHY and MAC layer considerations. We have thus used the implemented cross-layer simulator to evaluate the performance of MU-MIMO and compared it with the single-user MIMO (SU-MIMO). The aim of these studies was to evaluate the 'real' gains of MU-MIMO solutions (accounting for PHY+MAC) over SU-MIMO solutions and not the generally accepted ones. The impact of the channel sounding interval has particularly been studied. Finally, we have proposed a short PHY layer version of acknowledgment frames for overhead reduction in IEEE 802.11ah communications.

  5. Survivable Cloud Network Design Against Multiple Failures Through Protecting Spanning Trees

    NASA Astrophysics Data System (ADS)

    Zhou, Zhili; Lin, Tachun; Thulasiraman, Krishnaiyan

    2017-01-01

    Survivable design of cross-layer networks, such as the cloud computing infrastructure, lies in its resource deployment and allocation and mapping of the logical (virtual datacenter/IP) network into the physical infrastructure (cloud backbone/WDM) such that link or node failure(s) in the physical infrastructure would not result in cascading failures in the logical network. Most of the prior approaches for survivable cross-layer network design aim at single-link failure scenario, which are not applicable to the more challenging multi-failure scenarios. Also, as many of these approaches use the cross-layer cut concept, enumeration of all cuts in the network is required and thus introducing exponential number of constraints. To overcome these difficulties, we investigate in this paper survivable mapping approaches against multiple physical link failures and its special case, Shared Risk Link Group (SRLG) failure. We present the necessary and sufficient conditions based on both cross-layer spanning trees and cutsets to guarantee a survivable mapping when multiple physical link failures occur. Based on the necessary and sufficient conditions, we propose to solve the problem through (1) mixed-integer linear programs which avoid enumerating all combinations of link failures, and (2) an algorithm which generates/adds logical spanning trees sequentially. Our simulation results show that the proposed approaches can produce survivable mappings effectively against both $k$- and SRLG-failures.

  6. A Novel Cross-Layer Routing Protocol Based on Network Coding for Underwater Sensor Networks

    PubMed Central

    Wang, Hao; Wang, Shilian; Bu, Renfei; Zhang, Eryang

    2017-01-01

    Underwater wireless sensor networks (UWSNs) have attracted increasing attention in recent years because of their numerous applications in ocean monitoring, resource discovery and tactical surveillance. However, the design of reliable and efficient transmission and routing protocols is a challenge due to the low acoustic propagation speed and complex channel environment in UWSNs. In this paper, we propose a novel cross-layer routing protocol based on network coding (NCRP) for UWSNs, which utilizes network coding and cross-layer design to greedily forward data packets to sink nodes efficiently. The proposed NCRP takes full advantages of multicast transmission and decode packets jointly with encoded packets received from multiple potential nodes in the entire network. The transmission power is optimized in our design to extend the life cycle of the network. Moreover, we design a real-time routing maintenance protocol to update the route when detecting inefficient relay nodes. Substantial simulations in underwater environment by Network Simulator 3 (NS-3) show that NCRP significantly improves the network performance in terms of energy consumption, end-to-end delay and packet delivery ratio compared with other routing protocols for UWSNs. PMID:28786915

  7. Cross-Layer Adaptive Feedback Scheduling of Wireless Control Systems

    PubMed Central

    Xia, Feng; Ma, Longhua; Peng, Chen; Sun, Youxian; Dong, Jinxiang

    2008-01-01

    There is a trend towards using wireless technologies in networked control systems. However, the adverse properties of the radio channels make it difficult to design and implement control systems in wireless environments. To attack the uncertainty in available communication resources in wireless control systems closed over WLAN, a cross-layer adaptive feedback scheduling (CLAFS) scheme is developed, which takes advantage of the co-design of control and wireless communications. By exploiting cross-layer design, CLAFS adjusts the sampling periods of control systems at the application layer based on information about deadline miss ratio and transmission rate from the physical layer. Within the framework of feedback scheduling, the control performance is maximized through controlling the deadline miss ratio. Key design parameters of the feedback scheduler are adapted to dynamic changes in the channel condition. An event-driven invocation mechanism for the feedback scheduler is also developed. Simulation results show that the proposed approach is efficient in dealing with channel capacity variations and noise interference, thus providing an enabling technology for control over WLAN. PMID:27879934

  8. Multiple Segment Factorial Vignette Designs

    ERIC Educational Resources Information Center

    Ganong, Lawrence H.; Coleman, Marilyn

    2006-01-01

    The multiple segment factorial vignette design (MSFV) combines elements of experimental designs and probability sampling with the inductive, exploratory approach of qualitative research. MSFVs allow researchers to investigate topics that may be hard to study because of ethical or logistical concerns. Participants are presented with short stories…

  9. Multiple Segment Factorial Vignette Designs

    ERIC Educational Resources Information Center

    Ganong, Lawrence H.; Coleman, Marilyn

    2006-01-01

    The multiple segment factorial vignette design (MSFV) combines elements of experimental designs and probability sampling with the inductive, exploratory approach of qualitative research. MSFVs allow researchers to investigate topics that may be hard to study because of ethical or logistical concerns. Participants are presented with short stories…

  10. An MILP-Based Cross-Layer Optimization for a Multi-Reader Arbitration in the UHF RFID System

    PubMed Central

    Choi, Jinchul; Lee, Chaewoo

    2011-01-01

    In RFID systems, the performance of each reader such as interrogation range and tag recognition rate may suffer from interferences from other readers. Since the reader interference can be mitigated by output signal power control, spectral and/or temporal separation among readers, the system performance depends on how to adapt the various reader arbitration metrics such as time, frequency, and output power to the system environment. However, complexity and difficulty of the optimization problem increase with respect to the variety of the arbitration metrics. Thus, most proposals in previous study have been suggested to primarily prevent the reader collision with consideration of one or two arbitration metrics. In this paper, we propose a novel cross-layer optimization design based on the concept of combining time division, frequency division, and power control not only to solve the reader interference problem, but also to achieve the multiple objectives such as minimum interrogation delay, maximum reader utilization, and energy efficiency. Based on the priority of the multiple objectives, our cross-layer design optimizes the system sequentially by means of the mixed-integer linear programming. In spite of the multi-stage optimization, the optimization design is formulated as a concise single mathematical form by properly assigning a weight to each objective. Numerical results demonstrate the effectiveness of the proposed optimization design. PMID:22163743

  11. An MILP-based cross-layer optimization for a multi-reader arbitration in the UHF RFID system.

    PubMed

    Choi, Jinchul; Lee, Chaewoo

    2011-01-01

    In RFID systems, the performance of each reader such as interrogation range and tag recognition rate may suffer from interferences from other readers. Since the reader interference can be mitigated by output signal power control, spectral and/or temporal separation among readers, the system performance depends on how to adapt the various reader arbitration metrics such as time, frequency, and output power to the system environment. However, complexity and difficulty of the optimization problem increase with respect to the variety of the arbitration metrics. Thus, most proposals in previous study have been suggested to primarily prevent the reader collision with consideration of one or two arbitration metrics. In this paper, we propose a novel cross-layer optimization design based on the concept of combining time division, frequency division, and power control not only to solve the reader interference problem, but also to achieve the multiple objectives such as minimum interrogation delay, maximum reader utilization, and energy efficiency. Based on the priority of the multiple objectives, our cross-layer design optimizes the system sequentially by means of the mixed-integer linear programming. In spite of the multi-stage optimization, the optimization design is formulated as a concise single mathematical form by properly assigning a weight to each objective. Numerical results demonstrate the effectiveness of the proposed optimization design.

  12. Resource Allocation and Cross Layer Control in Wireless Networks

    DTIC Science & Technology

    2006-08-25

    nontrivial manner in order to support information transfer. In this paper we will present abstract models that capture the cross layer interaction from the...nontrivial manner in order to support information transfer. In this paper we will present abstract models that capture the cross layer inter- action from...parameters of the others. Our cross-layer model in this paper captures the interaction of these mechanisms, where all the physical and access layer

  13. Pyrochemical neutron multiplicity counter design

    SciTech Connect

    Langner, D.G.; Ensslin, N.; Krick, M.S.

    1990-01-01

    Pyrochemical process materials are difficult to measure using conventional neutron counting methods because of significant self- multiplication and variable ({alpha},n) reaction rates. Multiplicity counters measure the first three moments of the neutron multiplicity distribution and thus make it possible to determine sample mass even when multiplication and ({alpha},n) rate are unknown. A new multiplicity counter suitable for inplant measurement of pyrochemical process materials has been designed using Monte Carlo simulations. The goals were to produce a counter that has high neutron detection efficiency, low die-away time, a flat spatial efficiency profile, and is insensitive to the neutron energy spectrum. Monte Carlo calculations were performed for several prototype models consisting of four rings of 71-cm active length {sup 3}He tubes in a polyethylene body. The cadmium-lined sample well is 25 cm in diameter to accommodate a wide variety of inplant sample containers. The counter can be free-standing or in-line without mechanical modification. The calculations were performed to determine the above design criteria for several configurations of tube spacing, cadmium liners, and sample height. Calculations were also performed for distributed sample sources to understand the integrated effects of variable neutron spectra on the counter. 5 refs., 8 figs., 1 tab.

  14. Cross-layer optimization for wireless video communication

    NASA Astrophysics Data System (ADS)

    Wu, Dapeng; He, Zhihai

    2007-01-01

    With the rapid growth of wireless networks and increasing popularity of portable video devices, wireless video communication is poised to become the enabling technology for many multimedia applications over wireless networks. Real-time wireless video transmission typically has requirements on quality of service (QoS). However, wireless channels are unreliable and the channel capacities are time-varying, which may cause severe degradation to video presentation quality. In addition, for portable devices, video compression and wireless transmission are tightly coupled through the constraints on data rate, power, and delay. These issues make it particularly challenging to design an efficient real-time video compression and wireless transmission system on a portable device. In this paper, we take a cross-layer approach to this problem; our objective is to maximize the video quality under the constraints of resource and delay. Specifically, we minimize the end-to-end video distortion under the constraints of resource and delay, over the parameters in physical, link, and application (video) layers. This formulation is general and capable of capturing the fundamental aspects of the design of wireless video communication systems. Based on this formulation, we study how the resources could be intelligently allocated to maximize the video quality and analyze the performance limits of the wireless video communication system under resource constraints.

  15. Frame Transmission Efficiency-Based Cross-Layer Congestion Notification Scheme in Wireless Ad Hoc Networks

    PubMed Central

    He, Huaguang; Li, Taoshen; Feng, Luting; Ye, Jin

    2017-01-01

    Different from the traditional wired network, the fundamental cause of transmission congestion in wireless ad hoc networks is medium contention. How to utilize the congestion state from the MAC (Media Access Control) layer to adjust the transmission rate is core work for transport protocol design. However, recent works have shown that the existing cross-layer congestion detection solutions are too complex to be deployed or not able to characterize the congestion accurately. We first propose a new congestion metric called frame transmission efficiency (i.e., the ratio of successful transmission delay to the frame service delay), which describes the medium contention in a fast and accurate manner. We further present the design and implementation of RECN (ECN and the ratio of successful transmission delay to the frame service delay in the MAC layer, namely, the frame transmission efficiency), a general supporting scheme that adjusts the transport sending rate through a standard ECN (Explicit Congestion Notification) signaling method. Our method can be deployed on commodity switches with small firmware updates, while making no modification on end hosts. We integrate RECN transparently (i.e., without modification) with TCP on NS2 simulation. The experimental results show that RECN remarkably improves network goodput across multiple concurrent TCP flows. PMID:28714898

  16. Frame Transmission Efficiency-Based Cross-Layer Congestion Notification Scheme in Wireless Ad Hoc Networks.

    PubMed

    He, Huaguang; Li, Taoshen; Feng, Luting; Ye, Jin

    2017-07-15

    Different from the traditional wired network, the fundamental cause of transmission congestion in wireless ad hoc networks is medium contention. How to utilize the congestion state from the MAC (Media Access Control) layer to adjust the transmission rate is core work for transport protocol design. However, recent works have shown that the existing cross-layer congestion detection solutions are too complex to be deployed or not able to characterize the congestion accurately. We first propose a new congestion metric called frame transmission efficiency (i.e., the ratio of successful transmission delay to the frame service delay), which describes the medium contention in a fast and accurate manner. We further present the design and implementation of RECN (ECN and the ratio of successful transmission delay to the frame service delay in the MAC layer, namely, the frame transmission efficiency), a general supporting scheme that adjusts the transport sending rate through a standard ECN (Explicit Congestion Notification) signaling method. Our method can be deployed on commodity switches with small firmware updates, while making no modification on end hosts. We integrate RECN transparently (i.e., without modification) with TCP on NS2 simulation. The experimental results show that RECN remarkably improves network goodput across multiple concurrent TCP flows.

  17. Final report for CCS cross-layer reliability visioning study

    SciTech Connect

    Quinn, Heather M; Dehon, Andre; Carter, Nicj

    2010-12-20

    The geometric rate of improvement of transistor size and integrated circuit performance known as Moore's Law has been an engine of growth for our economy, enabling new products and services, creating new value and wealth, increasing safety, and removing menial tasks from our daily lives. Affordable, highly integrated components have enabled both life-saving technologies and rich entertainment applications. Anti-lock brakes, insulin monitors, and GPS-enabled emergency response systems save lives. Cell phones, internet appliances, virtual worlds, realistic video games, and mp3 players enrich our lives and connect us together. Over the past 40 years of silicon scaling, the increasing capabilities of inexpensive computation have transformed our society through automation and ubiquitous communications. Looking forward, increasing unpredictability threatens our ability to continue scaling integrated circuits at Moore's Law rates. As the transistors and wires that make up integrated circuits become smaller, they display both greater differences in behavior among devices designed to be identical and greater vulnerability to transient and permanent faults. Conventional design techniques expend energy to tolerate this unpredictability by adding safety margins to a circuit's operating voltage, clock frequency or charge stored per bit. However, the rising energy costs needed to compensate for increasing unpredictability are rapidly becoming unacceptable in today's environment where power consumption is often the limiting factor on integrated circuit performance and energy efficiency is a national concern. Reliability and energy consumption are both reaching key inflection points that, together, threaten to reduce or end the benefits of feature size reduction. To continue beneficial scaling, we must use a cross-layer, Jull-system-design approach to reliability. Unlike current systems, which charge every device a substantial energy tax in order to guarantee correct operation in

  18. On Internal Validity in Multiple Baseline Designs

    ERIC Educational Resources Information Center

    Pustejovsky, James E.

    2014-01-01

    Single-case designs are a class of research designs for evaluating intervention effects on individual cases. The designs are widely applied in certain fields, including special education, school psychology, clinical psychology, social work, and applied behavior analysis. The multiple baseline design (MBD) is the most frequently used single-case…

  19. Cross-Layer Design in Wireless Cognitive Networks (Postprint)

    DTIC Science & Technology

    2010-06-01

    24,2010 at 14:07:59 UTC from IEEE Xplore . Restrictions apply. 1 can be obtained by sharing of information across the layers of the protocol stack...Downloaded on June 24,2010 at 14:07:59 UTC from IEEE Xplore . Restrictions apply. 2 2. Cognitive Networks A cognitive infrastructure consists...24,2010 at 14:07:59 UTC from IEEE Xplore . Restrictions apply. 3 [16] discussed cognitive network management using reinforcement learning for

  20. Optimizing Airborne Networking Performance with Cross-Layer Design Approach

    DTIC Science & Technology

    2009-06-01

    b. ABSTRACT U c. THIS PAGE U 19b. TELEPHONE NUMBER (Include area code ) N/A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std...the link layer must adapt to the changes, by increasing the transmit power or using a better coding scheme. This would temporarily solve the problem...transport of compressed video. Video standards, such as MPEG [2] and H.263 [3], use motion- compensated predictive (MCP) coding to reduce the temporal

  1. Cooperative Communication Mechanism and Architecture for Cross-Layer Coordination

    DTIC Science & Technology

    2007-12-01

    receives the CTS and as a side effect can determine the quality of the channel. The sender’s MAC can use this information to set the transmission rate of...Figure 7 shows the process in detail. In step 0, the PHY receives some data and decodes it estimating the channel quality as a side effect . In step 1...be a system that we and other researchers can use effectively to validate a wide variety of cross-layer algorithms and protocols. 3

  2. A Cross-Layer PEP for DVB-RCS Networks

    NASA Astrophysics Data System (ADS)

    Giambene, Giovanni; Hadzic, Snezana

    The aim of this paper is to consider the problems of TCP performance in broadband GEO satellite networks and to propose a cross-layer approach for a transport-layer PEP that makes spoofing actions on ACKs to modify them in case the satellite network is congested. This approach is investigated here from the signaling standpoint with a special attention to the BSM reference model and considering a specific GEO satellite network architecture based on the DVB-S2/-RCS standards. The proposed PEP can prevent congestion in the satellite network, thus allowing a better TCP performance. This work has been carried out within the framework of the EU SatNEx II FP6 Network of Excellence.

  3. Testing Multiple Outcomes in Repeated Measures Designs

    ERIC Educational Resources Information Center

    Lix, Lisa M.; Sajobi, Tolulope

    2010-01-01

    This study investigates procedures for controlling the familywise error rate (FWR) when testing hypotheses about multiple, correlated outcome variables in repeated measures (RM) designs. A content analysis of RM research articles published in 4 psychology journals revealed that 3 quarters of studies tested hypotheses about 2 or more outcome…

  4. Testing Multiple Outcomes in Repeated Measures Designs

    ERIC Educational Resources Information Center

    Lix, Lisa M.; Sajobi, Tolulope

    2010-01-01

    This study investigates procedures for controlling the familywise error rate (FWR) when testing hypotheses about multiple, correlated outcome variables in repeated measures (RM) designs. A content analysis of RM research articles published in 4 psychology journals revealed that 3 quarters of studies tested hypotheses about 2 or more outcome…

  5. Vision for cross-layer optimization to address the dual challenges of energy and reliability

    SciTech Connect

    Quinn, Heather M; Dehon, Andre; Carter, Nicholas P

    2009-01-01

    We are rapidly approaching an inflection point where the conventional target of producing perfect, identical transistors that operate without upset can no longer be maintained while continuing to reduce the energy per operation. With power requirements already limiting chip performance, continuing to demand perfect, upset-free transistors would mean the end of scaling benefits. The big challenges in device variability and reliability are driven by uncommon tails in distributions, infrequent upsets, one-size-fits-all technology requirements, and a lack of information about the context of each operation. Solutions co-designed across traditional layer boundaries in our system stack can change the game, allowing architecture and software (a) to compensate for uncommon variation, environments, and events, (b) to pass down invariants and requirements for the computation, and (c) to monitor the health of collections of deVices. Cross-layer codesign provides a path to continue extracting benefits from further scaled technologies despite the fact that they may be less predictable and more variable. While some limited multi-layer mitigation strategies do exist, to move forward redefining traditional layer abstractions and developing a framework that facilitates cross-layer collaboration is necessary.

  6. Cross-layer ultrasound video streaming over mobile WiMAX and HSUPA networks.

    PubMed

    Alinejad, Ali; Philip, Nada Y; Istepanian, Robert S H

    2012-01-01

    It is well known that the evolution of 4G-based mobile multimedia network systems will contribute significantly to future mobile healthcare (m-health) applications that require high bandwidth and fast data rates. Central to the success of such emerging applications is the compatibility of broadband networks, such as mobile Worldwide Interoperability For Microwave Access (WiMAX) and High-Speed Uplink Packet Access (HSUPA), and especially their rate adaption issues combined with the acceptable real-time medical quality of service requirements. In this paper, we address the relevant challenges of cross-layer design requirements for real-time rate adaptation of ultrasound video streaming in mobile WiMAX and HSUPA networks. A comparative performance analysis of such approach is validated in two experimental m-health test bed systems for both mobile WiMAX and HSUPA networks. The experimental results have shown an improved performance of mobile WiMAX compared to the HSUPA using the same cross-layer optimization approach.

  7. Generating multiple new designs from a sketch

    SciTech Connect

    Stahovich, T.F.; Davis, R.; Shrobe, H.

    1996-12-31

    We describe a program called SKETCHIT that transforms a single sketch of a mechanical device into multiple families of new designs. It represents each of these families with a {open_quotes}BEP-Model,{close_quotes} a parametric model augmented with constraints that ensure the device produces the desired behavior. The program is based on qualitative configuration space (qc-space), a novel representation that captures mechanical behavior while abstracting away its implementation. The program employs a paradigm of abstraction and resynthesis: it abstracts the initial sketch into qc-space then maps from qc-space to new implementations.

  8. Simple design of multiple aerodynamic plasma actuator

    NASA Astrophysics Data System (ADS)

    Chernyshev, S. L.; Gamirullin, M. D.; Kuryachii, A. P.; Litvinov, V. M.

    2017-06-01

    A new simple design of multiple dielectric barrier discharge (DBD) actuator intended for gas §ow acceleration in thin boundary layer on lengthy aerodynamic surface is proposed. The operability of the considered multi-DBD-actuator is con¦rmed experimentally. Proposed method of measurements of the electric power consumed by the actuator permits to estimate this value simply and with acceptable accuracy. The thrust generated by DBD-actuator and thrust-to-power relation were estimated owing to pressure probe measurements of the induced §ow velocity.

  9. Design of Endoscopic Capsule With Multiple Cameras.

    PubMed

    Gu, Yingke; Xie, Xiang; Li, Guolin; Sun, Tianjia; Wang, Dan; Yin, Zheng; Zhang, Pengfei; Wang, Zhihua

    2015-08-01

    In order to reduce the miss rate of the wireless capsule endoscopy, in this paper, we propose a new system of the endoscopic capsule with multiple cameras. A master-slave architecture, including an efficient bus architecture and a four level clock management architecture, is applied for the Multiple Cameras Endoscopic Capsule (MCEC). For covering more area of the gastrointestinal tract wall with low power, multiple cameras with a smart image capture strategy, including movement sensitive control and camera selection, are used in the MCEC. To reduce the data transfer bandwidth and power consumption to prolong the MCEC's working life, a low complexity image compressor with PSNR 40.7 dB and compression rate 86% is implemented. A chipset is designed and implemented for the MCEC and a six cameras endoscopic capsule prototype is implemented by using the chipset. With the smart image capture strategy, the coverage rate of the MCEC prototype can achieve 98% and its power consumption is only about 7.1 mW.

  10. Design of a Multiple Input-Multiple Output Flight Control System Containing Uncertain Parameters.

    DTIC Science & Technology

    1984-11-01

    MULTIPLE INPUT - MULTIPLE OUTPUT ( MIMO ) SYSTEM... ......... 31 1. Introduction. ...................... 31 2...find design bounds analytically a (L) loop transmission i at flight condition j L nominal loop transmission 0 MIMO multiple input - multiple output M P...aircraft (12). The U. S. Air Force is interested in this technique as a method to * synthesize multiple input - multiple output ( MIMO ) controllers. In

  11. Designing small multiple-target artificial RNAs

    PubMed Central

    De Guire, Vincent; Caron, Maxime; Scott, Nicolas; Ménard, Catherine; Gaumont-Leclerc, Marie-France; Chartrand, Pascal; Major, François; Ferbeyre, Gerardo

    2010-01-01

    MicroRNAs (miRNAs) are naturally occurring small RNAs that regulate the expression of several genes. MiRNAs’ targeting rules are based on sequence complementarity between their mature products and targeted genes’ mRNAs. Based on our present understanding of those rules, we developed an algorithm to design artificial miRNAs to target simultaneously a set of predetermined genes. To validate in silico our algorithm, we tested different sets of genes known to be targeted by a single miRNA. The algorithm finds the seed of the corresponding miRNA among the solutions, which also include the seeds of new artificial miRNA sequences potentially capable of targeting these genes as well. We also validated the functionality of some artificial miRNAs designed to target simultaneously members of the E2F family. These artificial miRNAs reproduced the effects of E2Fs inhibition in both normal human fibroblasts and prostate cancer cells where they inhibited cell proliferation and induced cellular senescence. We conclude that the current miRNA targeting rules based on the seed sequence work to design multiple-target artificial miRNAs. This approach may find applications in both research and therapeutics. PMID:20453028

  12. Cross-layer optimization for video transmission over multirate GMC-CDMA wireless links.

    PubMed

    Bandyopadhyay, Saurav K; Partasides, George; Kondi, Lisimachos P

    2008-06-01

    In this paper, we consider the problem of video transmission over wireless generalized multicarrier code division multiple access (GMC-CDMA) systems. Such systems offer deterministic elimination of multiple access interference. A scalable video source codec is used and a multirate setup is assumed, i.e., each video user is allowed to occupy more than one GMC-CDMA channels. Furthermore, each of these channels can utilize a different number of subcarriers. We propose a cross-layer optimization method to select the source coding rate, channel coding rate, number of subcarriers per GMC-CDMA channel and transmission power per GMC-CDMA channel given a maximum transmission power for each video user and an available chip rate. Universal rate distortion characteristics (URDC) are used to approximate the expected distortion at the receiver. The proposed algorithm is optimal in the operational rate distortion sense, subject to the specific setup used and the approximation caused by the use of the URDC. Experimental results are presented and conclusions are drawn.

  13. MPACT Fast Neutron Multiplicity System Design Concepts

    SciTech Connect

    D. L. Chichester; S. A. Pozzi; J. L. Dolan; M. T. Kinlaw; A. C. Kaplan; M. Flaska; A. Enqvist; J. T. Johnsom; S. M. Watson

    2012-10-01

    This report documents work performed by Idaho National Laboratory and the University of Michigan in fiscal year (FY) 2012 to examine design parameters related to the use of fast-neutron multiplicity counting for assaying plutonium for materials protection, accountancy, and control purposes. This project seeks to develop a new type of neutron-measurement-based plutonium assay instrument suited for assaying advanced fuel cycle materials. Some current-concept advanced fuels contain high concentrations of plutonium; some of these concept fuels also contain other fissionable actinides besides plutonium. Because of these attributes the neutron emission rates of these new fuels may be much higher, and more difficult to interpret, than measurements made of plutonium-only materials. Fast neutron multiplicity analysis is one approach for assaying these advanced nuclear fuels. Studies have been performed to assess the conceptual performance capabilities of a fast-neutron multiplicity counter for assaying plutonium. Comparisons have been made to evaluate the potential improvements and benefits of fast-neutron multiplicity analyses versus traditional thermal-neutron counting systems. Fast-neutron instrumentation, using for example an array of liquid scintillators such as EJ-309, have the potential to either a) significantly reduce assay measurement times versus traditional approaches, for comparable measurement precision values, b) significantly improve assay precision values, for measurement durations comparable to current-generation technology, or c) moderating improve both measurement precision and measurement durations versus current-generation technology. Using the MCNPX-PoliMi Monte Carlo simulation code, studies have been performed to assess the doubles-detection efficiency for a variety of counter layouts of cylindrical liquid scintillator detector cells over one, two, and three rows. Ignoring other considerations, the best detector design is the one with the most

  14. Multiple-membrane multiple-electrolyte redox flow battery design

    DOEpatents

    Yan, Yushan; Gu, Shuang; Gong, Ke

    2017-05-02

    A redox flow battery is provided. The redox flow battery involves multiple-membrane (at least one cation exchange membrane and at least one anion exchange membrane), multiple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and at least one electrolyte disposed between the two membranes) as the basic characteristic, such as a double-membrane, triple electrolyte (DMTE) configuration or a triple-membrane, quadruple electrolyte (TMQE) configuration. The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte.

  15. Implementation of a Cross-Layer Sensing Medium-Access Control Scheme.

    PubMed

    Su, Yishan; Fu, Xiaomei; Han, Guangyao; Xu, Naishen; Jin, Zhigang

    2017-04-10

    In this paper, compressed sensing (CS) theory is utilized in a medium-access control (MAC) scheme for wireless sensor networks (WSNs). We propose a new, cross-layer compressed sensing medium-access control (CL CS-MAC) scheme, combining the physical layer and data link layer, where the wireless transmission in physical layer is considered as a compress process of requested packets in a data link layer according to compressed sensing (CS) theory. We first introduced using compressive complex requests to identify the exact active sensor nodes, which makes the scheme more efficient. Moreover, because the reconstruction process is executed in a complex field of a physical layer, where no bit and frame synchronizations are needed, the asynchronous and random requests scheme can be implemented without synchronization payload. We set up a testbed based on software-defined radio (SDR) to implement the proposed CL CS-MAC scheme practically and to demonstrate the validation. For large-scale WSNs, the simulation results show that the proposed CL CS-MAC scheme provides higher throughput and robustness than the carrier sense multiple access (CSMA) and compressed sensing medium-access control (CS-MAC) schemes.

  16. Cross-layer Energy Optimization Under Image Quality Constraints for Wireless Image Transmissions

    PubMed Central

    Yang, Na; Demirkol, Ilker; Heinzelman, Wendi

    2013-01-01

    Wireless image transmission is critical in many applications, such as surveillance and environment monitoring. In order to make the best use of the limited energy of the battery-operated cameras, while satisfying the application-level image quality constraints, cross-layer design is critical. In this paper, we develop an image transmission model that allows the application layer (e.g., the user) to specify an image quality constraint, and optimizes the lower layer parameters of transmit power and packet length, to minimize the energy dissipation in image transmission over a given distance. The effectiveness of this approach is evaluated by applying the proposed energy optimization to a reference ZigBee system and a WiFi system, and also by comparing to an energy optimization study that does not consider any image quality constraint. Evaluations show that our scheme outperforms the default settings of the investigated commercial devices and saves a significant amount of energy at middle-to-large transmission distances. PMID:23508852

  17. A cross-layer duty cycle MAC protocol supporting a pipeline feature for wireless sensor networks.

    PubMed

    Tong, Fei; Xie, Rong; Shu, Lei; Kim, Young-Chon

    2011-01-01

    Although the conventional duty cycle MAC protocols for Wireless Sensor Networks (WSNs) such as RMAC perform well in terms of saving energy and reducing end-to-end delivery latency, they were designed independently and require an extra routing protocol in the network layer to provide path information for the MAC layer. In this paper, we propose a new cross-layer duty cycle MAC protocol with data forwarding supporting a pipeline feature (P-MAC) for WSNs. P-MAC first divides the whole network into many grades around the sink. Each node identifies its grade according to its logical hop distance to the sink and simultaneously establishes a sleep/wakeup schedule using the grade information. Those nodes in the same grade keep the same schedule, which is staggered with the schedule of the nodes in the adjacent grade. Then a variation of the RTS/CTS handshake mechanism is used to forward data continuously in a pipeline fashion from the higher grade to the lower grade nodes and finally to the sink. No extra routing overhead is needed, thus increasing the network scalability while maintaining the superiority of duty-cycling. The simulation results in OPNET show that P-MAC has better performance than S-MAC and RMAC in terms of packet delivery latency and energy efficiency.

  18. A Cross-Layer Duty Cycle MAC Protocol Supporting a Pipeline Feature for Wireless Sensor Networks

    PubMed Central

    Tong, Fei; Xie, Rong; Shu, Lei; Kim, Young-Chon

    2011-01-01

    Although the conventional duty cycle MAC protocols for Wireless Sensor Networks (WSNs) such as RMAC perform well in terms of saving energy and reducing end-to-end delivery latency, they were designed independently and require an extra routing protocol in the network layer to provide path information for the MAC layer. In this paper, we propose a new cross-layer duty cycle MAC protocol with data forwarding supporting a pipeline feature (P-MAC) for WSNs. P-MAC first divides the whole network into many grades around the sink. Each node identifies its grade according to its logical hop distance to the sink and simultaneously establishes a sleep/wakeup schedule using the grade information. Those nodes in the same grade keep the same schedule, which is staggered with the schedule of the nodes in the adjacent grade. Then a variation of the RTS/CTS handshake mechanism is used to forward data continuously in a pipeline fashion from the higher grade to the lower grade nodes and finally to the sink. No extra routing overhead is needed, thus increasing the network scalability while maintaining the superiority of duty-cycling. The simulation results in OPNET show that P-MAC has better performance than S-MAC and RMAC in terms of packet delivery latency and energy efficiency. PMID:22163895

  19. Cross Layer PHY-MAC Protocol for Wireless Static and Mobile Ad Hoc Networks

    NASA Astrophysics Data System (ADS)

    Romaszko, Sylwia; Blondia, Chris

    2008-12-01

    Multihop mobile wireless networks have drawn a lot of attention in recent years thanks to their wide applicability in civil and military environments. Since the existing IEEE 802.11 distributed coordination function (DCF) standard does not provide satisfactory access to the wireless medium in multihop mobile networks, we have designed a cross-layer protocol, (CroSs-layer noise aware power driven MAC (SNAPdMac)), which consists of two parts. The protocol first concentrates on the flexible adjustment of the upper and lower bounds of the contention window (CW) to lower the number of collisions. In addition, it uses a power control scheme, triggered by the medium access control (MAC) layer, to limit the waste of energy and also to decrease the number of collisions. Thanks to a noticeable energy conservation and decrease of the number of collisions, it prolongs significantly the lifetime of the network and delays the death of the first node while increasing both the throughput performance and the sending bit rate/throughput fairness among contending flows.

  20. Design of a Ku band miniature multiple beam klystron

    SciTech Connect

    Bandyopadhyay, Ayan Kumar Pal, Debasish; Kant, Deepender; Saini, Anil; Saha, Sukalyan; Joshi, Lalit Mohan

    2016-03-09

    The design of a miniature multiple beam klystron (MBK) working in the Ku-band frequency range is presented in this article. Starting from the main design parameters, design of the electron gun, the input and output couplers and radio frequency section (RF-section) are presented. The design methodology using state of the art commercial electromagnetic design tools, analytical formulae as well as noncommercial design tools are briefly presented in this article.

  1. Design of a Ku band miniature multiple beam klystron

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, Ayan Kumar; Pal, Debasish; Saini, Anil; Kant, Deepender; Saha, Sukalyan; Joshi, Lalit Mohan

    2016-03-01

    The design of a miniature multiple beam klystron (MBK) working in the Ku-band frequency range is presented in this article. Starting from the main design parameters, design of the electron gun, the input and output couplers and radio frequency section (RF-section) are presented. The design methodology using state of the art commercial electromagnetic design tools, analytical formulae as well as noncommercial design tools are briefly presented in this article.

  2. Design Methodology for Multiple Microcomputer Architectures.

    DTIC Science & Technology

    1982-07-01

    multimicro design knowledge is true both in industry and in university environments. In the industrial environment, it reduces productivity and increases...Real-Time Processor Problems," Proc. of ELECTRO-81 Tercer Seminario de Ingenieria Electronica, Nov. 9-13, 1981. 14 1981 "D Flip/Flop Substracts

  3. Designing A Beam Waveguide For Multiple Frequencies

    NASA Technical Reports Server (NTRS)

    Galindo, Victor; Imbriale, William A.; Rengarajan, Sembiam R.

    1992-01-01

    Paper addresses defocusing and diffraction effects important in design of beam waveguide. Phase center of beam waveguide at lower frequency differs from focal point of geometric optics. If antenna system optimized for higher frequency, shift in phase center causes defocusing, with loss of signal at lower frequency. Defocusing caused by diffraction at lower frequencies reduced by shaping input pattern.

  4. Multiple Perspectives on Blended Learning Design

    ERIC Educational Resources Information Center

    Collis, Betty; Margaryan, Anoush; Amory, Marc

    2005-01-01

    Learning in the corporate setting not only relates to individual competence development but also to a demonstration of business impact and a contribution to the strategic ambitions of the company. An approach to learning design that blends generic principles of learning and instruction with strategic goals important to the particular context,…

  5. PrimerDesign-M: A multiple-alignment based multiple-primer design tool for walking across variable genomes

    SciTech Connect

    Yoon, Hyejin; Leitner, Thomas

    2014-12-17

    Analyses of entire viral genomes or mtDNA requires comprehensive design of many primers across their genomes. In addition, simultaneous optimization of several DNA primer design criteria may improve overall experimental efficiency and downstream bioinformatic processing. To achieve these goals, we developed PrimerDesign-M. It includes several options for multiple-primer design, allowing researchers to efficiently design walking primers that cover long DNA targets, such as entire HIV-1 genomes, and that optimizes primers simultaneously informed by genetic diversity in multiple alignments and experimental design constraints given by the user. PrimerDesign-M can also design primers that include DNA barcodes and minimize primer dimerization. PrimerDesign-M finds optimal primers for highly variable DNA targets and facilitates design flexibility by suggesting alternative designs to adapt to experimental conditions.

  6. PrimerDesign-M: A multiple-alignment based multiple-primer design tool for walking across variable genomes

    DOE PAGES

    Yoon, Hyejin; Leitner, Thomas

    2014-12-17

    Analyses of entire viral genomes or mtDNA requires comprehensive design of many primers across their genomes. In addition, simultaneous optimization of several DNA primer design criteria may improve overall experimental efficiency and downstream bioinformatic processing. To achieve these goals, we developed PrimerDesign-M. It includes several options for multiple-primer design, allowing researchers to efficiently design walking primers that cover long DNA targets, such as entire HIV-1 genomes, and that optimizes primers simultaneously informed by genetic diversity in multiple alignments and experimental design constraints given by the user. PrimerDesign-M can also design primers that include DNA barcodes and minimize primer dimerization. PrimerDesign-Mmore » finds optimal primers for highly variable DNA targets and facilitates design flexibility by suggesting alternative designs to adapt to experimental conditions.« less

  7. Assisting Design Given Multiple Performance Criteria

    DTIC Science & Technology

    1988-08-01

    by mapping an equational description of a common signal processing computation into a recurrence relation. The relationships between the input and...the plot, since 5 these transformations change the plot’s orientation and shape. They result in new tim- ing relationships , different numbers of...characteristics of the design to the system. The problem with this approach is the performance specifications are completely divorced from what is

  8. A survey on multimedia-based cross-layer optimization in visual sensor networks.

    PubMed

    Costa, Daniel G; Guedes, Luiz Affonso

    2011-01-01

    Visual sensor networks (VSNs) comprised of battery-operated electronic devices endowed with low-resolution cameras have expanded the applicability of a series of monitoring applications. Those types of sensors are interconnected by ad hoc error-prone wireless links, imposing stringent restrictions on available bandwidth, end-to-end delay and packet error rates. In such context, multimedia coding is required for data compression and error-resilience, also ensuring energy preservation over the path(s) toward the sink and improving the end-to-end perceptual quality of the received media. Cross-layer optimization may enhance the expected efficiency of VSNs applications, disrupting the conventional information flow of the protocol layers. When the inner characteristics of the multimedia coding techniques are exploited by cross-layer protocols and architectures, higher efficiency may be obtained in visual sensor networks. This paper surveys recent research on multimedia-based cross-layer optimization, presenting the proposed strategies and mechanisms for transmission rate adjustment, congestion control, multipath selection, energy preservation and error recovery. We note that many multimedia-based cross-layer optimization solutions have been proposed in recent years, each one bringing a wealth of contributions to visual sensor networks.

  9. A Survey on Multimedia-Based Cross-Layer Optimization in Visual Sensor Networks

    PubMed Central

    Costa, Daniel G.; Guedes, Luiz Affonso

    2011-01-01

    Visual sensor networks (VSNs) comprised of battery-operated electronic devices endowed with low-resolution cameras have expanded the applicability of a series of monitoring applications. Those types of sensors are interconnected by ad hoc error-prone wireless links, imposing stringent restrictions on available bandwidth, end-to-end delay and packet error rates. In such context, multimedia coding is required for data compression and error-resilience, also ensuring energy preservation over the path(s) toward the sink and improving the end-to-end perceptual quality of the received media. Cross-layer optimization may enhance the expected efficiency of VSNs applications, disrupting the conventional information flow of the protocol layers. When the inner characteristics of the multimedia coding techniques are exploited by cross-layer protocols and architectures, higher efficiency may be obtained in visual sensor networks. This paper surveys recent research on multimedia-based cross-layer optimization, presenting the proposed strategies and mechanisms for transmission rate adjustment, congestion control, multipath selection, energy preservation and error recovery. We note that many multimedia-based cross-layer optimization solutions have been proposed in recent years, each one bringing a wealth of contributions to visual sensor networks. PMID:22163908

  10. Cross-layer restoration with software defined networking based on IP over optical transport networks

    NASA Astrophysics Data System (ADS)

    Yang, Hui; Cheng, Lei; Deng, Junni; Zhao, Yongli; Zhang, Jie; Lee, Young

    2015-10-01

    The IP over optical transport network is a very promising networking architecture applied to the interconnection of geographically distributed data centers due to the performance guarantee of low delay, huge bandwidth and high reliability at a low cost. It can enable efficient resource utilization and support heterogeneous bandwidth demands in highly-available, cost-effective and energy-effective manner. In case of cross-layer link failure, to ensure a high-level quality of service (QoS) for user request after the failure becomes a research focus. In this paper, we propose a novel cross-layer restoration scheme for data center services with software defined networking based on IP over optical network. The cross-layer restoration scheme can enable joint optimization of IP network and optical network resources, and enhance the data center service restoration responsiveness to the dynamic end-to-end service demands. We quantitatively evaluate the feasibility and performances through the simulation under heavy traffic load scenario in terms of path blocking probability and path restoration latency. Numeric results show that the cross-layer restoration scheme improves the recovery success rate and minimizes the overall recovery time.

  11. SYSTEMATIC PROCEDURE FOR DESIGNING PROCESSES WITH MULTIPLE ENVIRONMENTAL OBJECTIVES

    EPA Science Inventory

    Evaluation of multiple objectives is very important in designing environmentally benign processes. It requires a systematic procedure for solving multiobjective decision-making problems, due to the complex nature of the problems, the need for complex assessments, and complicated ...

  12. SYSTEMATIC PROCEDURE FOR DESIGNING PROCESSES WITH MULTIPLE ENVIRONMENTAL OBJECTIVES

    EPA Science Inventory

    Evaluation of multiple objectives is very important in designing environmentally benign processes. It requires a systematic procedure for solving multiobjective decision-making problems, due to the complex nature of the problems, the need for complex assessments, and complicated ...

  13. EUROPA Multiple-Flyby Trajectory Design

    NASA Technical Reports Server (NTRS)

    Buffington, Brent; Campagnola, Stefano; Petropoulos, Anastassios

    2012-01-01

    As reinforced by the 2011 NRC Decadal Survey, Europa remains one of the most scientifically intriguing targets in planetary science due to its potential suitability for life. However, based on JEO cost estimates and current budgetary constraints, the Decadal Survey recommended-and later directed by NASA Headquarters-a more affordable pathway to Europa exploration be derived. In response, a flyby-only proof-of-concept trajectory has been developed to investigate Europa. The trajectory, enabled by employing a novel combination of new mission design techniques, successfully fulfills a set of Science Definition Team derived scientific objectives carried out by a notional payload including ice penetrating radar, topographic imaging, and short wavelength infrared observations, and ion neutral mass spectrometry in-situ measurements. The current baseline trajectory, referred to as 11-F5, consists of 34 Europa and 9 Ganymede flybys executed over the course of 2.4 years, reached a maximum inclination of 15 degrees, has a deterministic delta v of 157 m/s (post-PJR), and has a total ionizing dose of 2.06 Mrad (Si behind 100 mil Al, spherical shell). The 11-F5 trajectory and more generally speaking, flyby-only trajectories-exhibit a number of potential advantages over an Europa orbiter mission.

  14. EUROPA Multiple-Flyby Trajectory Design

    NASA Technical Reports Server (NTRS)

    Buffington, Brent; Campagnola, Stefano; Petropoulos, Anastassios

    2012-01-01

    As reinforced by the 2011 NRC Decadal Survey, Europa remains one of the most scientifically intriguing targets in planetary science due to its potential suitability for life. However, based on JEO cost estimates and current budgetary constraints, the Decadal Survey recommended-and later directed by NASA Headquarters-a more affordable pathway to Europa exploration be derived. In response, a flyby-only proof-of-concept trajectory has been developed to investigate Europa. The trajectory, enabled by employing a novel combination of new mission design techniques, successfully fulfills a set of Science Definition Team derived scientific objectives carried out by a notional payload including ice penetrating radar, topographic imaging, and short wavelength infrared observations, and ion neutral mass spectrometry in-situ measurements. The current baseline trajectory, referred to as 11-F5, consists of 34 Europa and 9 Ganymede flybys executed over the course of 2.4 years, reached a maximum inclination of 15 degrees, has a deterministic delta v of 157 m/s (post-PJR), and has a total ionizing dose of 2.06 Mrad (Si behind 100 mil Al, spherical shell). The 11-F5 trajectory and more generally speaking, flyby-only trajectories-exhibit a number of potential advantages over an Europa orbiter mission.

  15. An application of design knowledge captured from multiple sources

    NASA Technical Reports Server (NTRS)

    Cox, Preston A.; Forbes, John H.

    1990-01-01

    The Hubble Space Telescope Operational Readiness Expert Safemode Investigation System (HSTORESIS) is a reusable knowledge base shell used to demonstrate the integration and application of design knowledge captured from multiple technical domains. The design of HSTORESIS is based on a partitioning of knowledge to maximize the potential for reuse of certain types of knowledge.

  16. Design of Multiple Bolted Connections for Laminated Veneer Lumber

    Treesearch

    Borjen Yeh; Douglas Rammer; Jeff Linville

    2014-01-01

    The design of multiple bolted connections in accordance with Appendix E of the National Design Specification for Wood Construction (NDS) has incorporated provisions for evaluating localized member failure modes of row and group tear-out when the connections are closely spaced. Originally based on structural glued laminated timber (glulam) members made with all L1...

  17. PrimerDesign-M: a multiple-alignment based multiple-primer design tool for walking across variable genomes.

    PubMed

    Yoon, Hyejin; Leitner, Thomas

    2015-05-01

    Analyses of entire viral genomes or mtDNA requires comprehensive design of many primers across their genomes. Furthermore, simultaneous optimization of several DNA primer design criteria may improve overall experimental efficiency and downstream bioinformatic processing. To achieve these goals, we developed PrimerDesign-M. It includes several options for multiple-primer design, allowing researchers to efficiently design walking primers that cover long DNA targets, such as entire HIV-1 genomes, and that optimizes primers simultaneously informed by genetic diversity in multiple alignments and experimental design constraints given by the user. PrimerDesign-M can also design primers that include DNA barcodes and minimize primer dimerization. PrimerDesign-M finds optimal primers for highly variable DNA targets and facilitates design flexibility by suggesting alternative designs to adapt to experimental conditions. PrimerDesign-M is available as a webtool at http://www.hiv.lanl.gov/content/sequence/PRIMER_DESIGN/primer_design.html tkl@lanl.gov or seq-info@lanl.gov. Published by Oxford University Press 2014. This work is written by US Government employees and is in the public domain in the US.

  18. The Study of Cross-layer Optimization for Wireless Rechargeable Sensor Networks Implemented in Coal Mines.

    PubMed

    Ding, Xu; Shi, Lei; Han, Jianghong; Lu, Jingting

    2016-01-28

    Wireless sensor networks deployed in coal mines could help companies provide workers working in coal mines with more qualified working conditions. With the underground information collected by sensor nodes at hand, the underground working conditions could be evaluated more precisely. However, sensor nodes may tend to malfunction due to their limited energy supply. In this paper, we study the cross-layer optimization problem for wireless rechargeable sensor networks implemented in coal mines, of which the energy could be replenished through the newly-brewed wireless energy transfer technique. The main results of this article are two-fold: firstly, we obtain the optimal relay nodes' placement according to the minimum overall energy consumption criterion through the Lagrange dual problem and KKT conditions; secondly, the optimal strategies for recharging locomotives and wireless sensor networks are acquired by solving a cross-layer optimization problem. The cyclic nature of these strategies is also manifested through simulations in this paper.

  19. The Study of Cross-layer Optimization for Wireless Rechargeable Sensor Networks Implemented in Coal Mines

    PubMed Central

    Ding, Xu; Shi, Lei; Han, Jianghong; Lu, Jingting

    2016-01-01

    Wireless sensor networks deployed in coal mines could help companies provide workers working in coal mines with more qualified working conditions. With the underground information collected by sensor nodes at hand, the underground working conditions could be evaluated more precisely. However, sensor nodes may tend to malfunction due to their limited energy supply. In this paper, we study the cross-layer optimization problem for wireless rechargeable sensor networks implemented in coal mines, of which the energy could be replenished through the newly-brewed wireless energy transfer technique. The main results of this article are two-fold: firstly, we obtain the optimal relay nodes’ placement according to the minimum overall energy consumption criterion through the Lagrange dual problem and KKT conditions; secondly, the optimal strategies for recharging locomotives and wireless sensor networks are acquired by solving a cross-layer optimization problem. The cyclic nature of these strategies is also manifested through simulations in this paper. PMID:26828500

  20. IEEE 802.16 Packet Scheduling with Traffic Prioritization and Cross-Layer Optimization

    NASA Astrophysics Data System (ADS)

    Monteiro, João; Sargento, Susana; Gomes, Álvaro; Fontes, Francisco; Neves, Pedro

    WiMAX is emerging as a broadband wireless access technology to satisfy end user expectations, containing a new set of advantages in terms of throughput, coverage and QoS support at the MAC level which allows convergence of several different types of applications and services. For that reason, the allocation of resources or scheduling becomes of greater importance. This paper focuses on a cross-layer scheduling optimization solution for IEEE 802.16. The relevant features of the proposed packet scheduling optimization scheme consist: of prioritization of users within the same traffic class, allowing for example to an operator, differentiated treatment among users, for instance distinguishing between premium or gold users and silver users; and also cross layer optimization which implies radio resource optimization and a more effective scheduler decision. Simulation scenarios are presented to demonstrate how the scheduling solution allocates resources through particular WiMAX MAC layer implementation in the NS-2 simulator. Results show that the new mechanism implementation results in an improvement to the simple Round Robin fashion present in the original simulation model, being able to increase differentiation between different classes and decrease packets delay, due to its cross-layer processing and traffic prioritization.

  1. Design-Comparable Effect Sizes in Multiple Baseline Designs: A General Modeling Framework

    ERIC Educational Resources Information Center

    Pustejovsky, James E.; Hedges, Larry V.; Shadish, William R.

    2014-01-01

    In single-case research, the multiple baseline design is a widely used approach for evaluating the effects of interventions on individuals. Multiple baseline designs involve repeated measurement of outcomes over time and the controlled introduction of a treatment at different times for different individuals. This article outlines a general…

  2. Design-Comparable Effect Sizes in Multiple Baseline Designs: A General Modeling Framework

    ERIC Educational Resources Information Center

    Pustejovsky, James E.; Hedges, Larry V.; Shadish, William R.

    2014-01-01

    In single-case research, the multiple baseline design is a widely used approach for evaluating the effects of interventions on individuals. Multiple baseline designs involve repeated measurement of outcomes over time and the controlled introduction of a treatment at different times for different individuals. This article outlines a general…

  3. Additional comments on multiple-baseline designs in instructional research.

    PubMed

    Strain, P S; Shores, R E

    1979-11-01

    A number of measurement and design issues that are critical to the use of multiple-baseline procedures in evaluating instructional interventions were highlighted. First, issues related to the interaction between length of baseline assessment and the following outcomes were presented: (a) deceleration in behavior across baseline, (b) prediction of behavior change, (c) error analyses performance on instructional stimuli, and (d) reactivity of observation. Finally, an attempt was made to match the variety of multiple-baseline designs to specific questions often asked by instructional researchers.

  4. Maximized reliability with minimal cross-layer cutset under arbitrary link failure probability in multilayer optical networks

    NASA Astrophysics Data System (ADS)

    Zhao, Yongli; Chen, Bowen; Zhang, Jie

    2016-09-01

    We investigate the maximized cross-layer reliability under arbitrary link failure probability in multilayer optical networks. A concept of minimal cross-layer cutset is first defined and a reliability model with arbitrary physical link failure probability is built in the multilayer optical networks. In order to reduce the scale of cutset enumeration, we introduce two metrics to estimate cross-layer reliability, i.e., the minimum cross-layer node reliability and the minimum cross-layer edge reliability (MCER). Furthermore, we develop two linear programming (LP) models and two heuristic algorithms to maximize the cross-layer reliability of multilayer optical networks, i.e., the minimum shared-risk mapping algorithm and the least shared failure probability algorithm. Simulation results show that: (i) the cross-layer reliability of the two proposed algorithms is close to the LP solutions under logical networks with different sizes, which achieves better results in terms of additional resources utilization compared with the shortest path algorithm; (ii) less difference between the results of our proposed algorithms and the results of the shortest path algorithm is accompanied by a small standard deviation of failure probability distribution. Moreover, the superiority of our proposed algorithms becomes more remarkable with the increasing of the standard deviation.

  5. The multiple baseline design for evaluating population-based research.

    PubMed

    Hawkins, Nathan G; Sanson-Fisher, Robert W; Shakeshaft, Anthony; D'Este, Catherine; Green, Lawrence W

    2007-08-01

    There is a need for pragmatic and rigorous research designs to evaluate the effectiveness of population-based health interventions. The randomized controlled trial (RCT) has limitations in its practicality, ethical appropriateness, and cost when evaluating population-based interventions. Like RCTs, the multiple baseline design can demonstrate that a change in behavior has occurred, the change is a result of the intervention, and the change is significant. Especially important practical advantages over the RCT are that this design requires fewer population groups and communities may act as their own controls. Advantages and methodologic limitations of the multiple baseline design are discussed, and where feasible, strategies to minimize the impact of its limitations are suggested. Recommendations for future research are included.

  6. Design and analysis of multiple choice feeding preference data.

    PubMed

    Prince, Jeffrey S; LeBlanc, W G; Maciá, S

    2004-01-01

    Traditional analyses of feeding experiments that test consumer preference for an array of foods suffer from several defects. We have modified the experimental design to incorporate into a multivariate analysis the variance due to autogenic change in control replicates. Our design allows the multiple foods to be physically paired with their control counterparts. This physical proximity of the multiple food choices in control/experimental pairs ensures that the variance attributable to external environmental factors jointly affects all combinations within each replicate. Our variance term, therefore, is not a contrived estimate as is the case for the random pairing strategy proposed by previous studies. The statistical analysis then proceeds using standard multivariate statistical tests. We conducted a multiple choice feeding experiment using our experimental design and utilized a Monte Carlo analysis to compare our results with those obtained from an experimental design that employed the random pairing strategy. Our experimental design allowed detection of moderate differences among feeding means when the random design did not.

  7. The Steiner Multigraph Problem: Wildlife corridor design for multiple species

    Treesearch

    Katherine J. Lai; Carla P. Gomes; Michael K. Schwartz; Kevin S. McKelvey; David E. Calkin; Claire A. Montgomery

    2011-01-01

    The conservation of wildlife corridors between existing habitat preserves is important for combating the effects of habitat loss and fragmentation facing species of concern. We introduce the Steiner Multigraph Problem to model the problem of minimum-cost wildlife corridor design for multiple species with different landscape requirements. This problem can also model...

  8. A SYSTEMATIC PROCEDURE FOR DESIGNING PROCESSES WITH MULTIPLE ENVIRONMENTAL OBJECTIVES

    EPA Science Inventory

    Evaluation and analysis of multiple objectives are very important in designing environmentally benign processes. They require a systematic procedure for solving multi-objective decision-making problems due to the complex nature of the problems and the need for complex assessment....

  9. A SYSTEMATIC PROCEDURE FOR DESIGNING PROCESSES WITH MULTIPLE ENVIRONMENTAL OBJECTIVES

    EPA Science Inventory

    Evaluation and analysis of multiple objectives are very important in designing environmentally benign processes. They require a systematic procedure for solving multi-objective decision-making problems due to the complex nature of the problems and the need for complex assessment....

  10. Preliminary A{ampersand}PCT multiple detector design

    SciTech Connect

    Roberson, G. P.; Martz, H. E.; Camp, D. C.; Decman, D. J.; Johansson, E. M.

    1997-06-30

    The next generation, multi-detector active and passive computed tomography (A&PCT) scanner will be optimized for speed and accuracy. At the Lawrence Livermore National Lab (LLNL) we have demonstrated the trade-offs between different A&PCT design parameters that affect the speed and quality of the assay results. These fundamental parameters govern the optimum system design. Although the multi-detector scanner design has priority put on speed to increase waste drum throughput, higher speed should not compromise assay accuracy. One way to increase the speed of the A&PCT technology is to use multiple detectors. This yields a linear speedup by a factor approximately equal to the number of detectors used without a compromise in system accuracy. There are many different design scenarios that can be developed using multiple detectors. Here we describe four different scenarios and discuss the trade-offs between them. Also, some considerations are given in this design description for the implementation of a multiple detector technology in a field- deployable mobile trailer system.

  11. Automated platform for designing multiple robot work cells

    NASA Astrophysics Data System (ADS)

    Osman, N. S.; Rahman, M. A. A.; Rahman, A. A. Abdul; Kamsani, S. H.; Bali Mohamad, B. M.; Mohamad, E.; Zaini, Z. A.; Rahman, M. F. Ab; Mohamad Hatta, M. N. H.

    2017-06-01

    Designing the multiple robot work cells is very knowledge-intensive, intricate, and time-consuming process. This paper elaborates the development process of a computer-aided design program for generating the multiple robot work cells which offer a user-friendly interface. The primary purpose of this work is to provide a fast and easy platform for less cost and human involvement with minimum trial and errors adjustments. The automated platform is constructed based on the variant-shaped configuration concept with its mathematical model. A robot work cell layout, system components, and construction procedure of the automated platform are discussed in this paper where integration of these items will be able to automatically provide the optimum robot work cell design according to the information set by the user. This system is implemented on top of CATIA V5 software and utilises its Part Design, Assembly Design, and Macro tool. The current outcomes of this work provide a basis for future investigation in developing a flexible configuration system for the multiple robot work cells.

  12. Towards Robust Designs Via Multiple-Objective Optimization Methods

    NASA Technical Reports Server (NTRS)

    Man Mohan, Rai

    2006-01-01

    Fabricating and operating complex systems involves dealing with uncertainty in the relevant variables. In the case of aircraft, flow conditions are subject to change during operation. Efficiency and engine noise may be different from the expected values because of manufacturing tolerances and normal wear and tear. Engine components may have a shorter life than expected because of manufacturing tolerances. In spite of the important effect of operating- and manufacturing-uncertainty on the performance and expected life of the component or system, traditional aerodynamic shape optimization has focused on obtaining the best design given a set of deterministic flow conditions. Clearly it is important to both maintain near-optimal performance levels at off-design operating conditions, and, ensure that performance does not degrade appreciably when the component shape differs from the optimal shape due to manufacturing tolerances and normal wear and tear. These requirements naturally lead to the idea of robust optimal design wherein the concept of robustness to various perturbations is built into the design optimization procedure. The basic ideas involved in robust optimal design will be included in this lecture. The imposition of the additional requirement of robustness results in a multiple-objective optimization problem requiring appropriate solution procedures. Typically the costs associated with multiple-objective optimization are substantial. Therefore efficient multiple-objective optimization procedures are crucial to the rapid deployment of the principles of robust design in industry. Hence the companion set of lecture notes (Single- and Multiple-Objective Optimization with Differential Evolution and Neural Networks ) deals with methodology for solving multiple-objective Optimization problems efficiently, reliably and with little user intervention. Applications of the methodologies presented in the companion lecture to robust design will be included here. The

  13. A centrifugal pump concept designed for multiple use in space

    NASA Astrophysics Data System (ADS)

    Wunderlich, E.; Wulz, H. G.

    A centrifugal pump concept was elaborated for a multiple application in future spacecrafts. Based on this concept a prototype of a small centrifugal pump was manufactured and comprehensively tested. The model pump has been approved in different test series with the fluids liquid ammonia and demineralized water. The design of the model pump was driven by strict requirements of COLUMBUS, namely long life, noiseless operation, minimum mass and low energy consumption. Because of its modular design and as a result of selected materials of multiple compatibility, this pump is suited for the delivery of various further fluids, such as freons, hydrocarbons, propellants (hydrazine) etc.. It is also capable of pumping corrosive or toxic fluids for laboratory processes in space. The wide speed range from about 1,00 to 20,000 rpm which corresponds to a flow from about 1 to 20 l/min, permits an energy saving adaption and flow control.

  14. Designing multiple-choice test items at higher cognitive levels.

    PubMed

    Su, Whei Ming; Osisek, Paul J; Montgomery, Cynthia; Pellar, Suzanne

    2009-01-01

    In the midst of a nursing faculty shortage, many academic institutions hire clinicians who are not formally prepared for an academic role. These novice faculty face an immediate need to develop teaching skills. One area in particular is test construction. To address this need, the authors describe how faculty from one course designed multiple-choice test items at higher cognitive levels and simultaneously achieved congruence with critical-thinking learning objectives defined by the course.

  15. On the Design and Analysis of Multiple-Storage Elements

    DTIC Science & Technology

    1989-12-01

    PROjECT TASK ORK UN!T ELEMENT NO NO NO ACCESSION NO 11 TITLE (Include Security Classification) ON THE DESIGN AND ANALYSIS OF MULTIPLE-VALUED STORAGE...the degree of MASTER OF SCIENCE IN ELECTRICAL ENGINEERING f: om the NAVAL POSTGRADUATE SCHOOL December 1989 Aurhor: David AMork Approved by: / Jon T...Butler, Thesis Advisor )~hn P. Powers, Chairman Department of Electrical and Computer Engineering 11 ABSTRACT The primary contribution of this thesis

  16. A Research Proposal on Cognitive Opportunistic Communications and Cognitive Cross-layer Protocol Stack Design

    DTIC Science & Technology

    2012-07-23

    identify the technology being used (e.g., ZigBee vs. Bluetooth , vs. IEEE 802.11), and is therefore a useful tool on which cognitive behaviors can be built...occupancies, as well as to withstand the loss of packets due to randomly hopping jammers , and has been shown by extensive numerical evaluations to... Bluetooth , vs. IEEE 802.11), and is therefore a useful tool on which cognitive behaviors can be built. Management tools are very important for the

  17. Cross-Layer Design for Robust and Scalable Video Transmission in Dynamic Wireless Environment

    DTIC Science & Technology

    2011-02-01

    CNR for Several Beta Values 64- QAM ........................................... 47 Table 19 Illustrate the Calculations for the Different Modulation ... modulation at the physical layer to the bit streams with different QoS requirements at the application layer. Unfortunately, for most non-binary...quadrature amplitude modulation ( QAM ) and hierarchical phase shift keying (PSK) modulation schemes in terms of exponential and complementary error

  18. SCTPmx: An SCTP Fast Handover Mechanism Using a Single Interface Based on a Cross-Layer Architecture

    NASA Astrophysics Data System (ADS)

    Han, Yunsop; Teraoka, Fumio

    Recently, SCTP is attracting attention to support mobility in the Internet because it does not require additional equipment such as the Home Agent of Mobile IP. This paper focuses on an SCTP fast handover mechanism using a single interface because it is assumed that small mobile devices have a single interface per communication medium such as IEEE802.11b due to hardware limitations. The proposed mechanism called SCTPmx employs a cross layer control information exchange system called LIESto predict handover. LIES was originally designed to achieve network layer fast handover and then it was extended by adding the network layer primitives for efficient interaction among the link layer, the network layer, and the transport layer. Prior to handover, SCTPmx can generate a new address that will be used after handover and can execute duplicate address detection of IPv6. SCTPmx can suppress the delay caused by channel scanning at the link layer by employing selective background scanning mechanism which allows to continue data communication during channel scanning. In addition, SCTPmx can notify the correspondent node of the new address before handover. SCTPmx was implemented on FreeBSD. SCTPmx achieved better than 25 times lower handover latency (100msec) and 2 times higher throughput than previous proposals.

  19. A Cross-Layer User Centric Vertical Handover Decision Approach Based on MIH Local Triggers

    NASA Astrophysics Data System (ADS)

    Rehan, Maaz; Yousaf, Muhammad; Qayyum, Amir; Malik, Shahzad

    Vertical handover decision algorithm that is based on user preferences and coupled with Media Independent Handover (MIH) local triggers have not been explored much in the literature. We have developed a comprehensive cross-layer solution, called Vertical Handover Decision (VHOD) approach, which consists of three parts viz. mechanism for collecting and storing user preferences, Vertical Handover Decision (VHOD) algorithm and the MIH Function (MIHF). MIHF triggers the VHOD algorithm which operates on user preferences to issue handover commands to mobility management protocol. VHOD algorithm is an MIH User and therefore needs to subscribe events and configure thresholds for receiving triggers from MIHF. In this regard, we have performed experiments in WLAN to suggest thresholds for Link Going Down trigger. We have also critically evaluated the handover decision process, proposed Just-in-time interface activation technique, compared our proposed approach with prominent user centric approaches and analyzed our approach from different aspects.

  20. Railway network design with multiple project stages and time sequencing

    NASA Astrophysics Data System (ADS)

    Kuby, Michael; Xu, Zhongyi; Xie, Xiaodong

    This paper presents a spatial decision support system for network design problems in which different kinds of projects can be built in stages over time. It was developed by the World Bank and China's Ministry of Railways to plan investment strategies for China's overburdened railway system. We first present a mixed-integer program for the single-period network design problem with project choices such as single or multiple tracks and/or electrification with economies of scale. Then, because such projects can be built all at once or in stages, we developed a heuristic backwards time sequencing procedure with a cost adjustment factor to solve the ``project staging'' problem. Other innovations include a preloading routine; coordinated modeling of arcs, paths, and corridors; and a custom-built GIS.

  1. Design and performances of the Scrap Neutron Multiplicity Counter

    NASA Astrophysics Data System (ADS)

    Marin Ferrer, Montserrat; Peerani, Paolo; Looman, Marc R.; Dechamp, Luc

    2007-05-01

    JRC has developed the Scrap Neutron Multiplicity Counter (SNMC): an advanced neutron multiplicity counter for the verification of inhomogeneous Pu samples, such as scrap material in MOX fuel fabrication plants. The innovative features of this counter with respect to existing ones rely on two aspects: (i) an optimised design based on Monte Carlo calculations in order to select the most appropriate materials, geometry and detector disposition for maximum efficiency and (ii) novel electronics based on digital signal processing (DSP) reducing the system dead time. The paper recalls the design process, the electronics, the construction and assembly of the counter. Then the results of the first experimental tests will be reported. We will show the characterization of the main physical parameters of the counter, the calibration and the verification of a wide variety of plutonium bearing samples available in the PERLA laboratory at JRC Ispra. This will include pure homogeneous samples (Pu dioxide powders, metal Pu, MOX powders and pellets) and some tests on heterogeneous samples representative of scrap material.

  2. Design and modeling of small scale multiple fracturing experiments

    SciTech Connect

    Cuderman, J F

    1981-12-01

    Recent experiments at the Nevada Test Site (NTS) have demonstrated the existence of three distinct fracture regimes. Depending on the pressure rise time in a borehole, one can obtain hydraulic, multiple, or explosive fracturing behavior. The use of propellants rather than explosives in tamped boreholes permits tailoring of the pressure risetime over a wide range since propellants having a wide range of burn rates are available. This technique of using the combustion gases from a full bore propellant charge to produce controlled borehole pressurization is termed High Energy Gas Fracturing (HEGF). Several series of HEGF, in 0.15 m and 0.2 m diameter boreholes at 12 m depths, have been completed in a tunnel complex at NTS where mineback permitted direct observation of fracturing obtained. Because such large experiments are costly and time consuming, smaller scale experiments are desirable, provided results from small experiments can be used to predict fracture behavior in larger boreholes. In order to design small scale gas fracture experiments, the available data from previous HEGF experiments were carefully reviewed, analytical elastic wave modeling was initiated, and semi-empirical modeling was conducted which combined predictions for statically pressurized boreholes with experimental data. The results of these efforts include (1) the definition of what constitutes small scale experiments for emplacement in a tunnel complex at the Nevada Test Site, (2) prediction of average crack radius, in ash fall tuff, as a function of borehole size and energy input per unit length, (3) definition of multiple-hydraulic and multiple-explosive fracture boundaries as a function of boreholes size and surface wave velocity, (4) semi-empirical criteria for estimating stress and acceleration, and (5) a proposal that multiple fracture orientations may be governed by in situ stresses.

  3. Shielding design for multiple-energy linear accelerators.

    PubMed

    Barish, Robert J

    2014-05-01

    The introduction of medical linear accelerators (linacs) capable of producing three different x-ray energies has complicated the process of designing shielding for these units. The conventional approach for the previous generation of dual-energy linacs relied on the addition of some amount of supplementary shielding to that calculated for the higher-energy beam, where the amount of that supplement followed the historical "two-source" rule, also known as the "add one HVL rule," a practice derived from other two-source shielding considerations. The author describes an iterative approach that calculates shielding requirements accurately for any number of multiple beam energies assuming the workload at each energy can be specified at the outset. This method is particularly useful when considering the requirements for possible modifications to an existing vault when new equipment is to be installed as a replacement for a previous unit.

  4. Conservatism implications of shock test tailoring for multiple design environments

    NASA Technical Reports Server (NTRS)

    Baca, Thomas J.; Bell, R. Glenn; Robbins, Susan A.

    1987-01-01

    A method for analyzing shock conservation in test specifications that have been tailored to qualify a structure for multiple design environments is discussed. Shock test conservation is qualified for shock response spectra, shock intensity spectra and ranked peak acceleration data in terms of an Index of Conservation (IOC) and an Overtest Factor (OTF). The multi-environment conservation analysis addresses the issue of both absolute and average conservation. The method is demonstrated in a case where four laboratory tests have been specified to qualify a component which must survive seven different field environments. Final judgment of the tailored test specification is shown to require an understanding of the predominant failure modes of the test item.

  5. Design and fabrication of multiple airgap-based visible filters

    NASA Astrophysics Data System (ADS)

    Ghaderi, M.; Wolffenbuttel, R. F.

    2014-05-01

    The efficiency of a Bragg reflector design for implementation in optical resonators is highly dependent on the ratio between the high-index material and the low-index material used for the quarter-wavelength (QWOT) layers. A higher contrast implies that fewer layers are required to achieve a specified spectral selectivity over a wider spectral band. In turn, the reduced total thickness of the filter stack reduces the effect of optical absorption in the layers. The research presented here focuses on implementation of filters on top of silicon detectors that are already fabricated in a CMOS process. This implies that the constraints of process compatibility, such as the materials to be used, process temperature and cleanroom reentrance related to contamination, need to be considered. Silicon-dioxide is often used in CMOS-compatible designs, which has an index of refraction n~1.5, thus limiting nHi/nLo to about 2. This value can be improved by 50% when using air-films as the low-n material. Surface micromachining is used for the fabrication of such mirrors. Multiple layers of Si and SiO2 were alternatingly deposited, and subsequently the Si layers are selectively removed in a sacrificial etch. The width of the λ/4 air-gaps is about 100 nm, which is narrower as compared to the typical layer thickness that is used in surface micromachining for conventional MEMS applications. Moreover, a demanding optical design requires more layers than typically used in a conventional MEMS device. Since the number of stacked layers is significantly higher as compared to the conventional MEMS, fabricating such filters is a challenge. However, unlike a conventional MEMS, electrical contacting to the structural layers is not required in optical filter application, which, eases the fabrication of such filters. This paper presents the design of several 4-layer structures for use in the visible spectral range, along with the fabrication sequence and preliminary measurement results.

  6. Design of Spacecraft Missions to Remove Multiple Orbital Debris Objects

    NASA Technical Reports Server (NTRS)

    Barbee, Brent W.; Alfano, Salvatore; Pinon, Elfego; Gold, Kenn; Gaylor, David

    2012-01-01

    The amount of hazardous debris in Earth orbit has been increasing, posing an evergreater danger to space assets and human missions. In January of 2007, a Chinese ASAT test produced approximately 2600 pieces of orbital debris. In February of 2009, Iridium 33 collided with an inactive Russian satellite, yielding approximately 1300 pieces of debris. These recent disastrous events and the sheer size of the Earth orbiting population make clear the necessity of removing orbital debris. In fact, experts from both NASA and ESA have stated that 10 to 20 pieces of orbital debris need to be removed per year to stabilize the orbital debris environment. However, no spacecraft trajectories have yet been designed for removing multiple debris objects and the size of the debris population makes the design of such trajectories a daunting task. Designing an efficient spacecraft trajectory to rendezvous with each of a large number of orbital debris pieces is akin to the famous Traveling Salesman problem, an NP-complete combinatorial optimization problem in which a number of cities are to be visited in turn. The goal is to choose the order in which the cities are visited so as to minimize the total path distance traveled. In the case of orbital debris, the pieces of debris to be visited must be selected and ordered such that spacecraft propellant consumption is minimized or at least kept low enough to be feasible. Emergent Space Technologies, Inc. has developed specialized algorithms for designing efficient tour missions for near-Earth asteroids that may be applied to the design of efficient spacecraft missions capable of visiting large numbers of orbital debris pieces. The first step is to identify a list of high priority debris targets using the Analytical Graphics, Inc. SOCRATES website and then obtain their state information from Celestrak. The tour trajectory design algorithms will then be used to determine the itinerary of objects and v requirements. These results will shed light

  7. On Locating Multiple Interacting Quantitative Trait Loci in Intercross Designs

    PubMed Central

    Baierl, Andreas; Bogdan, Małgorzata; Frommlet, Florian; Futschik, Andreas

    2006-01-01

    A modified version (mBIC) of the Bayesian Information Criterion (BIC) has been previously proposed for backcross designs to locate multiple interacting quantitative trait loci. In this article, we extend the method to intercross designs. We also propose two modifications of the mBIC. First we investigate a two-stage procedure in the spirit of empirical Bayes methods involving an adaptive (i.e., data-based) choice of the penalty. The purpose of the second modification is to increase the power of detecting epistasis effects at loci where main effects have already been detected. We investigate the proposed methods by computer simulations under a wide range of realistic genetic models, with nonequidistant marker spacings and missing data. In the case of large intermarker distances we use imputations according to Haley and Knott regression to reduce the distance between searched positions to not more than 10 cM. Haley and Knott regression is also used to handle missing data. The simulation study as well as real data analyses demonstrates good properties of the proposed method of QTL detection. PMID:16624924

  8. Cross-layer active predictive congestion control protocol for wireless sensor networks.

    PubMed

    Wan, Jiangwen; Xu, Xiaofeng; Feng, Renjian; Wu, Yinfeng

    2009-01-01

    In wireless sensor networks (WSNs), there are numerous factors that may cause network congestion problems, such as the many-to-one communication modes, mutual interference of wireless links, dynamic changes of network topology and the memory-restrained characteristics of nodes. All these factors result in a network being more vulnerable to congestion. In this paper, a cross-layer active predictive congestion control scheme (CL-APCC) for improving the performance of networks is proposed. Queuing theory is applied in the CL-APCC to analyze data flows of a single-node according to its memory status, combined with the analysis of the average occupied memory size of local networks. It also analyzes the current data change trends of local networks to forecast and actively adjust the sending rate of the node in the next period. In order to ensure the fairness and timeliness of the network, the IEEE 802.11 protocol is revised based on waiting time, the number of the node's neighbors and the original priority of data packets, which dynamically adjusts the sending priority of the node. The performance of CL-APCC, which is evaluated by extensive simulation experiments. is more efficient in solving the congestion in WSNs. Furthermore, it is clear that the proposed scheme has an outstanding advantage in terms of improving the fairness and lifetime of networks.

  9. Cross-Layer Algorithms for QoS Enhancement in Wireless Multimedia Sensor Networks

    NASA Astrophysics Data System (ADS)

    Saxena, Navrati; Roy, Abhishek; Shin, Jitae

    A lot of emerging applications like advanced telemedicine and surveillance systems, demand sensors to deliver multimedia content with precise level of QoS enhancement. Minimizing energy in sensor networks has been a much explored research area but guaranteeing QoS over sensor networks still remains an open issue. In this letter we propose a cross-layer approach combining Network and MAC layers, for QoS enhancement in wireless multimedia sensor networks. In the network layer a statistical estimate of sensory QoS parameters is performed and a nearoptimal genetic algorithmic solution is proposed to solve the NP-complete QoS-routing problem. On the other hand the objective of the proposed MAC algorithm is to perform the QoS-based packet classification and automatic adaptation of the contention window. Simulation results demonstrate that the proposed protocol is capable of providing lower delay and better throughput, at the cost of reasonable energy consumption, in comparison with other existing sensory QoS protocols.

  10. Cross-Layer Active Predictive Congestion Control Protocol for Wireless Sensor Networks

    PubMed Central

    Wan, Jiangwen; Xu, Xiaofeng; Feng, Renjian; Wu, Yinfeng

    2009-01-01

    In wireless sensor networks (WSNs), there are numerous factors that may cause network congestion problems, such as the many-to-one communication modes, mutual interference of wireless links, dynamic changes of network topology and the memory-restrained characteristics of nodes. All these factors result in a network being more vulnerable to congestion. In this paper, a cross-layer active predictive congestion control scheme (CL-APCC) for improving the performance of networks is proposed. Queuing theory is applied in the CL-APCC to analyze data flows of a single-node according to its memory status, combined with the analysis of the average occupied memory size of local networks. It also analyzes the current data change trends of local networks to forecast and actively adjust the sending rate of the node in the next period. In order to ensure the fairness and timeliness of the network, the IEEE 802.11 protocol is revised based on waiting time, the number of the node's neighbors and the original priority of data packets, which dynamically adjusts the sending priority of the node. The performance of CL-APCC, which is evaluated by extensive simulation experiments. is more efficient in solving the congestion in WSNs. Furthermore, it is clear that the proposed scheme has an outstanding advantage in terms of improving the fairness and lifetime of networks. PMID:22408506

  11. Constraints of nonresponding flows based on cross layers in the networks

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi-Chao; Xiao, Yang; Wang, Dong

    2016-02-01

    In the active queue management (AQM) scheme, core routers cannot manage and constrain user datagram protocol (UDP) data flows by the sliding window control mechanism in the transport layer due to the nonresponsive nature of such traffic flows. However, the UDP traffics occupy a large part of the network service nowadays which brings a great challenge to the stability of the more and more complex networks. To solve the uncontrollable problem, this paper proposes a cross layers random early detection (CLRED) scheme, which can control the nonresponding UDP-like flows rate effectively when congestion occurs in the access point (AP). The CLRED makes use of the MAC frame acknowledgement (ACK) transmitting congestion information to the sources nodes and utilizes the back-off windows of the MAC layer throttling data rate. Consequently, the UDP-like flows data rate can be restrained timely by the sources nodes in order to alleviate congestion in the complex networks. The proposed CLRED can constrain the nonresponsive flows availably and make the communication expedite, so that the network can sustain stable. The simulation results of network simulator-2 (NS2) verify the proposed CLRED scheme.

  12. The Efficacy of the Cycles Approach: A Multiple Baseline Design

    PubMed Central

    Rudolph, Johanna M.; Wendt, Oliver

    2014-01-01

    The purpose of this study was to evaluate the efficacy of the Cycles Phonological Remediation Approach as an intervention for children with speech sound disorders (SSD). A multiple baseline design across behaviors was used to examine intervention effects. Three children (ages 4;3 to 5;3) with moderate-severe to severe SSDs participated in two cycles of therapy. Three phonological patterns were targeted for each child. Generalization probes were administered during baseline, intervention, and follow-up phases to assess generalization and maintenance of learned skills. Two of the three participants exhibited statistically and clinically significant gains by the end of the intervention phase and these effects were maintained at follow-up. The third participant exhibited significant gains at follow-up. Phonologically known target patterns showed greater generalization than unknown target patterns across all phases. Individual differences in performance were examined at the participant level and the target pattern level. Learner Outcomes The reader will be able to: (1) enumerate the three major components of the cycles approach, (2) describe factors that should be considered when selecting treatment targets, and (3) identify variables that may affect a child’s outcome following cycles treatment PMID:24438911

  13. The efficacy of the cycles approach: a multiple baseline design.

    PubMed

    Rudolph, Johanna M; Wendt, Oliver

    2014-01-01

    The purpose of this study was to evaluate the efficacy of the Cycles Phonological Remediation Approach as an intervention for children with speech sound disorders (SSD). A multiple baseline design across behaviors was used to examine intervention effects. Three children (ages 4;3 to 5;3) with moderate-severe to severe SSDs participated in two cycles of therapy. Three phonological patterns were targeted for each child. Generalization probes were administered during baseline, intervention, and follow-up phases to assess generalization and maintenance of learned skills. Two of the three participants exhibited statistically and clinically significant gains by the end of the intervention phase and these effects were maintained at follow-up. The third participant exhibited significant gains at follow-up. Phonologically known target patterns showed greater generalization than unknown target patterns across all phases. Individual differences in performance were examined at the participant level and the target pattern level. The reader will be able to: (1) enumerate the three major components of the cycles approach, (2) describe factors that should be considered when selecting treatment targets, and (3) identify variables that may affect a child's outcome following cycles treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Teachers and parents as researchers using multiple baseline designs1

    PubMed Central

    Hall, R. Vance; Cristler, Connie; Cranston, Sharon S.; Tucker, Bonnie

    1970-01-01

    Two teachers and a parent used three basic multiple baseline designs to investigate the effects of systematic reinforcement and punishment procedures in the classroom and at home. (1) A fifth-grade teacher concurrently measured the same behavior (tardiness) in three stimulus situations (after morning, noon, and afternoon recesses). Posting the names of pupils on a chart titled “Today's Patriots” was made contingent on being on time after the noon recess, then successively also the morning and afternoon recesses. Tardiness was reduced to near zero rates at the points where contingencies were applied. (2) A highschool teacher recorded the same behavior (daily French-quiz grades) of three students. She then successively applied the same consequences (staying after school for individual tutoring for D and F grades) for each student. At the points where the contingency was applied, D and F grades were eliminated. (3) A mother concurrently measured three different behaviors (clarinet practice, Campfire project work, reading) of her 10-yr-old daughter. She successively applied the same contingency (going to bed early) for less than 30 min spent engaged in one after another of the behaviors. Marked increases in the behaviors were observed at the points where the contingency was applied. PMID:16795265

  15. Multiple Path Interference and Its Impact on System Design

    NASA Astrophysics Data System (ADS)

    Bromage, J.; Winzer, P. J.; Essiambre, R.-J.

    Lightwave communication systems carry information that is encoded onto the intensity, phase, or polarization of light from one point to another along an optical path. When designing such systems, many mechanisms that degrade the transfer of information must be taken into account. Until the late 1990s, the main causes of signal degradation in transmission were fiber nonlinearity and amplified spontaneous emission (ASE) from optical amplifiers. More recently, however, a third type of system degradation, involving the unwanted beating of the signal with a number of weak interferers, has become increasingly important. With reference to Fig. 15.1(a), such interferers can result from imperfect extinction of the drop-signal in optical cross-connects and add-drop multiplexers, which are both key elements for flexible and transparent optical network architectures [1,2]. Also, single-Rayleigh backscattering in bidirectional transmission systems [3, 4] can lead to unwanted interferers at the receiver. Although these two examples involve interferers that are independent of the main signal, the important class of multiple-path interference (MPI) involves interferers that are delayed replicas of the main signal. In the case of MPI, additional (unwanted) optical paths, with losses orders of magnitude greater than the main path, lead to interfering signals at the receiver, and can have a significant impact on system performance. With reference to Figs. 15.1 (b) and 15.1(c), MPI is encountered for

  16. Cross-layer cluster-based energy-efficient protocol for wireless sensor networks.

    PubMed

    Mammu, Aboobeker Sidhik Koyamparambil; Hernandez-Jayo, Unai; Sainz, Nekane; de la Iglesia, Idoia

    2015-04-09

    Recent developments in electronics and wireless communications have enabled the improvement of low-power and low-cost wireless sensors networks (WSNs). One of the most important challenges in WSNs is to increase the network lifetime due to the limited energy capacity of the network nodes. Another major challenge in WSNs is the hot spots that emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. In such an environment, cross-layer cluster-based energy-efficient algorithms (CCBE) can prolong the network lifetime and energy efficiency. CCBE is based on clustering the nodes to different hexagonal structures. A hexagonal cluster consists of cluster members (CMs) and a cluster head (CH). The CHs are selected from the CMs based on nodes near the optimal CH distance and the residual energy of the nodes. Additionally, the optimal CH distance that links to optimal energy consumption is derived. To balance the energy consumption and the traffic load in the network, the CHs are rotated among all CMs. In WSNs, energy is mostly consumed during transmission and reception. Transmission collisions can further decrease the energy efficiency. These collisions can be avoided by using a contention-free protocol during the transmission period. Additionally, the CH allocates slots to the CMs based on their residual energy to increase sleep time. Furthermore, the energy consumption of CH can be further reduced by data aggregation. In this paper, we propose a data aggregation level based on the residual energy of CH and a cost-aware decision scheme for the fusion of data. Performance results show that the CCBE scheme performs better in terms of network lifetime, energy consumption and throughput compared to low-energy adaptive clustering hierarchy (LEACH) and hybrid energy-efficient distributed clustering (HEED).

  17. Cross-Layer Cluster-Based Energy-Efficient Protocol for Wireless Sensor Networks

    PubMed Central

    Mammu, Aboobeker Sidhik Koyamparambil; Hernandez-Jayo, Unai; Sainz, Nekane; de la Iglesia, Idoia

    2015-01-01

    Recent developments in electronics and wireless communications have enabled the improvement of low-power and low-cost wireless sensors networks (WSNs). One of the most important challenges in WSNs is to increase the network lifetime due to the limited energy capacity of the network nodes. Another major challenge in WSNs is the hot spots that emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. In such an environment, cross-layer cluster-based energy-efficient algorithms (CCBE) can prolong the network lifetime and energy efficiency. CCBE is based on clustering the nodes to different hexagonal structures. A hexagonal cluster consists of cluster members (CMs) and a cluster head (CH). The CHs are selected from the CMs based on nodes near the optimal CH distance and the residual energy of the nodes. Additionally, the optimal CH distance that links to optimal energy consumption is derived. To balance the energy consumption and the traffic load in the network, the CHs are rotated among all CMs. In WSNs, energy is mostly consumed during transmission and reception. Transmission collisions can further decrease the energy efficiency. These collisions can be avoided by using a contention-free protocol during the transmission period. Additionally, the CH allocates slots to the CMs based on their residual energy to increase sleep time. Furthermore, the energy consumption of CH can be further reduced by data aggregation. In this paper, we propose a data aggregation level based on the residual energy of CH and a cost-aware decision scheme for the fusion of data. Performance results show that the CCBE scheme performs better in terms of network lifetime, energy consumption and throughput compared to low-energy adaptive clustering hierarchy (LEACH) and hybrid energy-efficient distributed clustering (HEED). PMID:25860073

  18. Cross-Layer Scheme to Control Contention Window for Per-Flow in Asymmetric Multi-Hop Networks

    NASA Astrophysics Data System (ADS)

    Giang, Pham Thanh; Nakagawa, Kenji

    The IEEE 802.11 MAC standard for wireless ad hoc networks adopts Binary Exponential Back-off (BEB) mechanism to resolve bandwidth contention between stations. BEB mechanism controls the bandwidth allocation for each station by choosing a back-off value from one to CW according to the uniform random distribution, where CW is the contention window size. However, in asymmetric multi-hop networks, some stations are disadvantaged in opportunity of access to the shared channel and may suffer severe throughput degradation when the traffic load is large. Then, the network performance is degraded in terms of throughput and fairness. In this paper, we propose a new cross-layer scheme aiming to solve the per-flow unfairness problem and achieve good throughput performance in IEEE 802.11 multi-hop ad hoc networks. Our cross-layer scheme collects useful information from the physical, MAC and link layers of own station. This information is used to determine the optimal Contention Window (CW) size for per-station fairness. We also use this information to adjust CW size for each flow in the station in order to achieve per-flow fairness. Performance of our cross-layer scheme is examined on various asymmetric multi-hop network topologies by using Network Simulator (NS-2).

  19. Undergraduate Design Learning in Multiple Partnerships: For Academies

    ERIC Educational Resources Information Center

    Butcher, John; Schaber, Friedemann

    2013-01-01

    This article reports research into undergraduate design learning through an off-campus partnership. The Sorrell Foundation's Joinedupdesign for Academies programme involved partnerships between university design departments, "failing" 11-18 schools and professional designers, in the context of a funding commitment to rebuild/renew school…

  20. Undergraduate Design Learning in Multiple Partnerships: For Academies

    ERIC Educational Resources Information Center

    Butcher, John; Schaber, Friedemann

    2013-01-01

    This article reports research into undergraduate design learning through an off-campus partnership. The Sorrell Foundation's Joinedupdesign for Academies programme involved partnerships between university design departments, "failing" 11-18 schools and professional designers, in the context of a funding commitment to rebuild/renew school…

  1. Tether-mission design for multiple flybys of moon Europa

    NASA Astrophysics Data System (ADS)

    Sanmartin, J. R. S.; Charro, M. C.; Sanchez-Arriaga, G. S. A.; Sanchez-Torres, A. S. T.

    2015-10-01

    A tether mission to carry out multiple flybys of Jovian moon Europa is here presented. There is general agreement on elliptic-orbit flybys of Europa resulting in cost to attain given scientific goals lower than if actually orbiting the moon, tethers being naturally fit to fly-by rather than orbit moons1. The present mission is similar in this respect to the Clipper mission considered by NASA, the basic difference lying in location of periapsis, due to different emphasis on mission-challenge metrics. Clipper minimizes damaging radiation-dose by avoiding the Jupiter neighborhood and its very harsh environment; periapsis would be at Europa, apoapsis as far as moon Callisto. As in all past outer-planet missions, Clipper faces, however, critical power and propulsion needs. On the other hand, tethers can provide both propulsion and power, but must reach near the planet to find high plasma density and magnetic field values, leading to high induced tether current, and Lorentz drag and power. The bottom line is a strong radiation dose under the very intense Radiation Belts of Jupiter. Mission design focuses on limiting dose. Perijove would be near Jupiter, at about 1.2-1.3 Jovian radius, apojove about moon Ganymede, corresponding to 1:1 resonance with Europa, so as to keep dose down: setting apojove at Europa, for convenient parallel flybys, would require two perijove passes per flyby (the Ganymede apojove, resulting in high eccentricity, about 0.86, is also less requiring on tether operations). Mission is designed to attain reductions in eccentricity per perijove pass as high as Δe ≈ - 0.04. Due the low gravity-gradient, tether spinning is necessary to keep it straight, plasma contactors placed at both ends taking active turns at being cathodic. Efficiency of capture of the incoming S/C by the tether is gauged by the ratio of S/C mass to tether mass; efficiency is higher for higher tape-tether length and lower thickness and perijove. Low tether bowing due to the Lorentz

  2. Design and development of oral nanoparticulated insulin in multiple emulsion.

    PubMed

    Siddhartha, T Venkata; Senthil, V; Kishan, Ilindra Sai; Khatwal, Rizwan Basha; Madhunapantula, SubbaRao V

    2014-01-01

    The present research aimed at developing an injection-free nanoparticulated formulation in multiple emulsion form, for oral delivery of insulin, which otherwise undergoes degradation in the gastric environment if administered orally. Insulin-polymeric nanoparticles were prepared using layer by layer (LbL) adsorption method and incorporated into an emulsion to form a nanoparticulated multiple emulsion. Using 0.6 M sodium chloride, the insulin nanoaggregates of 300-400 nm size were obtained about a yield of 94%. The characteristics of a representative nanoparticle were as follows: particle size - 391.9±0.41 nm, polydispersity index -0.425, zeta potential- +20.6 mv, encapsulation efficiency- 86.7±1.42% and percentage entrapment efficiency of the insulin-polymeric nanoparticles in the inner aqueous phase of emulsion was 84.6%. The FT-IR analysis confirms that there were no drug interactions with the polymers. Stability analysis carried out for 3 months at 8-40 °C, showed only minor changes at the end period. The release kinetics of the nanoparticulated multiple emulsion at pH 7.4 followed first order kinetics and obeyed the Fickian law. However, at pH 2.0 the release kinetics from nanoparticulated multiple emulsion followed zero order kinetics without obeying to the Fickian law. In conclusion, our data demonstrate that the nanoparticulated multiple emulsion formulation has good release characteristics and imparted a tolerable protection for insulin at different pH conditions, which may be exploited for oral administration.

  3. Estimation of a Nonlinear Intervention Phase Trajectory for Multiple-Baseline Design Data

    ERIC Educational Resources Information Center

    Hembry, Ian; Bunuan, Rommel; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim

    2015-01-01

    A multilevel logistic model for estimating a nonlinear trajectory in a multiple-baseline design is introduced. The model is applied to data from a real multiple-baseline design study to demonstrate interpretation of relevant parameters. A simple change-in-levels (?"Levels") model and a model involving a quadratic function…

  4. A Design Study to Develop Young Children's Understanding of Multiplication and Division

    ERIC Educational Resources Information Center

    Bicknell, Brenda; Young-Loveridge, Jenny; Nguyen, Nhung

    2016-01-01

    This design study investigated the use of multiplication and division problems to help 5-year-old children develop an early understanding of multiplication and division. One teacher and her class of 15 5-year-old children were involved in a collaborative partnership with the researchers. The design study was conducted over two 4-week periods in…

  5. Minimum Fuel Trajectory Design in Multiple Dynamical Environments Utilizing Direct Transcription Methods and Particle Swarm Optimization

    DTIC Science & Technology

    2016-03-01

    MINIMUM-FUEL TRAJECTORY DESIGN IN MULTIPLE DYNAMICAL ENVIRONMENTS UTILIZING DIRECT TRANSCRIPTION METHODS AND PARTICLE SWARM OPTIMIZATION THESIS...250 MINIMUM-FUEL TRAJECTORY DESIGN IN MULTIPLE DYNAMICAL ENVIRONMENTS UTILIZING DIRECT TRANSCRIPTION METHODS AND PARTICLE SWARM OPTIMIZATION THESIS... Education and Training Command in Partial Fulfillment of the Requirements for the Degree of Master of Science in Astronautical Engineering Alfredo G

  6. Estimation of a Nonlinear Intervention Phase Trajectory for Multiple-Baseline Design Data

    ERIC Educational Resources Information Center

    Hembry, Ian; Bunuan, Rommel; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim

    2015-01-01

    A multilevel logistic model for estimating a nonlinear trajectory in a multiple-baseline design is introduced. The model is applied to data from a real multiple-baseline design study to demonstrate interpretation of relevant parameters. A simple change-in-levels (?"Levels") model and a model involving a quadratic function…

  7. The Multiple Roles of the Task Design Mediator in Telecollaboration

    ERIC Educational Resources Information Center

    Fuchs, Carolin; Snyder, Bill; Tung, Bruce; Jung Han, Yu

    2017-01-01

    This case study explores how a Chinese-American novice teacher acted as mediator in a telecollaboration with student teacher (ST) peers in the USA who designed tasks for his English as a foreign language (EFL) learners in China. The novice teacher was instrumental in mediating the student teachers' task design process by providing feedback…

  8. Regression Discontinuity Designs with Multiple Rating-Score Variables

    ERIC Educational Resources Information Center

    Reardon, Sean F.; Robinson, Joseph P.

    2012-01-01

    In the absence of a randomized control trial, regression discontinuity (RD) designs can produce plausible estimates of the treatment effect on an outcome for individuals near a cutoff score. In the standard RD design, individuals with rating scores higher than some exogenously determined cutoff score are assigned to one treatment condition; those…

  9. Learning Design Rashomon II: Exploring One Lesson through Multiple Tools

    ERIC Educational Resources Information Center

    Prieto, Luis P.; Dimitriadis, Yannis; Craft, Brock; Derntl, Michael; Emin, Valerie; Katsamani, Mary; Laurillard, Diana; Masterman, Elizabeth; Retalis, Symeon; Villasclaras, Eloy

    2013-01-01

    An increasing number of tools are available to support the learning design process at different levels and from different perspectives. However, this variety can make it difficult for researchers and teachers to assess the tool that is best suited to their objectives and contexts as learning designers. Several of the tools are presented elsewhere…

  10. Regression Discontinuity Designs with Multiple Rating-Score Variables

    ERIC Educational Resources Information Center

    Reardon, Sean F.; Robinson, Joseph P.

    2012-01-01

    In the absence of a randomized control trial, regression discontinuity (RD) designs can produce plausible estimates of the treatment effect on an outcome for individuals near a cutoff score. In the standard RD design, individuals with rating scores higher than some exogenously determined cutoff score are assigned to one treatment condition; those…

  11. RNAblueprint: flexible multiple target nucleic acid sequence design.

    PubMed

    Hammer, Stefan; Tschiatschek, Birgit; Flamm, Christoph; Hofacker, Ivo L; Findeiß, Sven

    2017-09-15

    Realizing the value of synthetic biology in biotechnology and medicine requires the design of molecules with specialized functions. Due to its close structure to function relationship, and the availability of good structure prediction methods and energy models, RNA is perfectly suited to be synthetically engineered with predefined properties. However, currently available RNA design tools cannot be easily adapted to accommodate new design specifications. Furthermore, complicated sampling and optimization methods are often developed to suit a specific RNA design goal, adding to their inflexibility. We developed a C ++  library implementing a graph coloring approach to stochastically sample sequences compatible with structural and sequence constraints from the typically very large solution space. The approach allows to specify and explore the solution space in a well defined way. Our library also guarantees uniform sampling, which makes optimization runs performant by not only avoiding re-evaluation of already found solutions, but also by raising the probability of finding better solutions for long optimization runs. We show that our software can be combined with any other software package to allow diverse RNA design applications. Scripting interfaces allow the easy adaption of existing code to accommodate new scenarios, making the whole design process very flexible. We implemented example design approaches written in Python to demonstrate these advantages. RNAblueprint , Python implementations and benchmark datasets are available at github: https://github.com/ViennaRNA . s.hammer@univie.ac.at, ivo@tbi.univie.ac.at or sven@tbi.univie.ac.at. Supplementary data are available at Bioinformatics online.

  12. Multiple methods integration for structural mechanics analysis and design

    NASA Technical Reports Server (NTRS)

    Housner, J. M.; Aminpour, M. A.

    1991-01-01

    A new research area of multiple methods integration is proposed for joining diverse methods of structural mechanics analysis which interact with one another. Three categories of multiple methods are defined: those in which a physical interface are well defined; those in which a physical interface is not well-defined, but selected; and those in which the interface is a mathematical transformation. Two fundamental integration procedures are presented that can be extended to integrate various methods (e.g., finite elements, Rayleigh Ritz, Galerkin, and integral methods) with one another. Since the finite element method will likely be the major method to be integrated, its enhanced robustness under element distortion is also examined and a new robust shell element is demonstrated.

  13. Supporting Affect Regulation in Children with Multiple Disabilities during Psychotherapy: A Multiple Case Design Study of Therapeutic Attachment

    ERIC Educational Resources Information Center

    Schuengel, C.; Sterkenburg, P. S.; Jeczynski, P.; Janssen, C. G. C.; Jongbloed, G.

    2009-01-01

    In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist…

  14. Supporting Affect Regulation in Children with Multiple Disabilities during Psychotherapy: A Multiple Case Design Study of Therapeutic Attachment

    ERIC Educational Resources Information Center

    Schuengel, C.; Sterkenburg, P. S.; Jeczynski, P.; Janssen, C. G. C.; Jongbloed, G.

    2009-01-01

    In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist…

  15. Source-circuit design with multiple photovoltaic manufacturers

    NASA Technical Reports Server (NTRS)

    Spencer, R.

    1983-01-01

    The problems associated with source circuit design for use in photovoltaic (PV) hardware of different manufacturers or processes are discussed. The varying performance of dissimilar materials is examined and the need for standardization of equipment and performance output is investigated.

  16. Multiple IMU system hardware interface design, volume 2

    NASA Technical Reports Server (NTRS)

    Landey, M.; Brown, D.

    1975-01-01

    The design of each system component is described. Emphasis is placed on functional requirements unique in this system, including data bus communication, data bus transmitters and receivers, and ternary-to-binary torquing decision logic. Mechanization drawings are presented.

  17. Launch Vehicle Propulsion Parameter Design Multiple Selection Criteria

    NASA Technical Reports Server (NTRS)

    Shelton, Joey Dewayne

    2004-01-01

    The optimization tool described herein addresses and emphasizes the use of computer tools to model a system and focuses on a concept development approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system, but more particularly the development of the optimized system using new techniques. This methodology uses new and innovative tools to run Monte Carlo simulations, genetic algorithm solvers, and statistical models in order to optimize a design concept. The concept launch vehicle and propulsion system were modeled and optimized to determine the best design for weight and cost by varying design and technology parameters. Uncertainty levels were applied using Monte Carlo Simulations and the model output was compared to the National Aeronautics and Space Administration Space Shuttle Main Engine. Several key conclusions are summarized here for the model results. First, the Gross Liftoff Weight and Dry Weight were 67% higher for the design case for minimization of Design, Development, Test and Evaluation cost when compared to the weights determined by the minimization of Gross Liftoff Weight case. In turn, the Design, Development, Test and Evaluation cost was 53% higher for optimized Gross Liftoff Weight case when compared to the cost determined by case for minimization of Design, Development, Test and Evaluation cost. Therefore, a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Secondly, the tool outputs define the sensitivity of propulsion parameters, technology and cost factors and how these parameters differ when cost and weight are optimized separately. A key finding was that for a Space Shuttle Main Engine thrust level the oxidizer/fuel ratio of 6.6 resulted in the lowest Gross Liftoff Weight rather than at 5.2 for the maximum specific impulse, demonstrating the relationships between specific impulse, engine weight, tank volume and tank weight. Lastly, the optimum chamber pressure for

  18. Launch Vehicle Propulsion Design with Multiple Selection Criteria

    NASA Technical Reports Server (NTRS)

    Shelton, Joey D.; Frederick, Robert A.; Wilhite, Alan W.

    2005-01-01

    The approach and techniques described herein define an optimization and evaluation approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system. The method uses Monte Carlo simulations, genetic algorithm solvers, a propulsion thermo-chemical code, power series regression curves for historical data, and statistical models in order to optimize a vehicle system. The system, including parameters for engine chamber pressure, area ratio, and oxidizer/fuel ratio, was modeled and optimized to determine the best design for seven separate design weight and cost cases by varying design and technology parameters. Significant model results show that a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Other key findings show the sensitivity of propulsion parameters, technology factors, and cost factors and how these parameters differ when cost and weight are optimized separately. Each of the three key propulsion parameters; chamber pressure, area ratio, and oxidizer/fuel ratio, are optimized in the seven design cases and results are plotted to show impacts to engine mass and overall vehicle mass.

  19. Design of multiple-ply laminated composite tapered beams

    NASA Technical Reports Server (NTRS)

    Rodriguez, P.

    1993-01-01

    A study of a special case of symmetric laminated composite cantilever beams is presented. The approach models beams that are tapered both in depth and width and investigates the effect of the ply layup angle and the ply taper on bending and interlaminar shearing stresses. For the determination of stresses and deflections, the beam stiffness matrices are expressed as linear functions of the beam length. Using classical lamination theory (CLT) the stiffness matrices are determined and assembled at strategic locations along the length of the beam. They are then inverted and necessary stiffness parameters are obtained numerically and extracted for determination of design information at each location chosen. Several ply layup configurations are investigated, and design considerations are presented based on the findings. Finally, recommendations for the design of these beams are presented, and a means for anticipating the location of highest stresses is offered.

  20. Concept and design of a multiple-function laser (MFL)

    NASA Astrophysics Data System (ADS)

    Karning, Heinrich; Ruger, James F.; Weispfenning, Martin

    1998-10-01

    The multifunctional properties of modern Laser sources for future military sensor applications will be studied. The goal of this study is the design of a modular laser source which covers various functions like: Laser rangefinding. Target designation (1.06 micrometer), Eyesafe target designation (1.5 micrometer), Laser radar for Automatic target recognition, Identification friend or foe using Laser interrogation with D- band response as well as allowance for Covert communication and Missile jamming with a laser in the 3 to 5 micrometer range. It is obvious that these applications require a wide range of power levels, wavelength agility and pulse repetition rates. The concept for a compact Laser source to cover these requirements will be presented. In addition a concept for the integrated sensor to provide the above mentioned functions will also be presented.

  1. The Analysis of Repeated Measures Designs Involving Multiple Dependent Variables.

    ERIC Educational Resources Information Center

    Schutz, Robert W.; Gessaroli, Marc E.

    1987-01-01

    The article discusses the concepts and interpretations for four methods of testing differences among means in a mixed model repeated measures design. The four methods discussed are: traditional ANOVA and the MANOVA methods for the single dependent variable case, and a Multivariate Mixed Model analysis and a Doubly Multivariate analysis for the…

  2. Percutaneous multiple electrode connector, design parameters and fabrication (biomedical)

    NASA Technical Reports Server (NTRS)

    Myers, L. A.

    1977-01-01

    A percutaneous multielectrode connector was designed which utilizes an ultrapure carbon collar to provide an infection free biocompatible passage through the skin. The device provides reliable electrical continuity, mates and demates readily with the implant, and is fabricated with processes and materials oriented to commercial production.

  3. Including Multiple Voices in Collaboratively Designing a Teacher Education Program

    ERIC Educational Resources Information Center

    Konecki, Loretta R.; Sturdivant, Robika L.; King, Caryn M.; Melin, Jacquelyn A.; Lancaster, Paula E.

    2012-01-01

    This narrative case study describes the collaborative processes employed by a midwestern university as it designed and implemented a clinically based, postbaccalaureate teacher preparation program for science, technology, engineering, and mathematics (STEM) graduates committed to teaching in high need secondary schools. The program development…

  4. Designing Undergraduate Research Experiences: A Multiplicity of Options

    NASA Astrophysics Data System (ADS)

    Manduca, C. A.

    2001-12-01

    Research experiences for undergraduate students can serve many goals including: developing student understanding of the process of science; providing opportunities for students to develop professional skills or test career plans; completing publishable research; enabling faculty professional development; or enhancing the visibility of a science program. The large range of choices made in the design of an undergraduate research program or opportunity must reflect the goals of the program, the needs and abilities of the students and faculty, and the available resources including both time and money. Effective program design, execution, and evaluation can all be enhanced if the goals of the program are clearly articulated. Student research experiences can be divided into four components: 1) defining the research problem; 2) developing the research plan or experiment design; 3) collecting and interpreting data, and 4) communicating results. In each of these components, the program can be structured in a wide variety of ways and students can be given more or less guidance or freedom. While a feeling of ownership of the research project appears to be very important, examples of successful projects displaying a wide range of design decisions are available. Work with the Keck Geology Consortium suggests that four strategies can enhance the likelihood of successful student experiences: 1) students are well-prepared for research experience (project design must match student preparation); 2) timelines and events are structured to move students through intermediate goals to project completion; 3) support for the emotional, financial, academic and technical challenges of a research project is in place; 4) strong communications between students and faculty set clear expectations and enable mid-course corrections in the program or project design. Creating a research culture for the participants or embedding a project in an existing research culture can also assist students in

  5. GSFC conceptual design study for an inter-satellite Optical Multiple Access communication system

    NASA Technical Reports Server (NTRS)

    Fox, Neil; Maynard, Will; Clarke, Ernest; Bruno, Ronald

    1991-01-01

    System and terminal level specifications for an inter-satellite Optical Multiple Access (OMA) communication system are presented, as well as the resulting hardware designs for both OMA relay and OMA user terminals. The OMA relay terminal design uses a mechanical innovation which moves multiple fiber optic pickups in the focal plane, thereby providing simultaneous links with multiple OMA user terminals via a single telescope. Thus, with such a terminal on a relay satellite, multiple access service can be provided with a minimum of impact on the relay satellite.

  6. GSFC conceptual design study for an inter-satellite Optical Multiple Access communication system

    NASA Technical Reports Server (NTRS)

    Fox, Neil; Maynard, Will; Clarke, Ernest; Bruno, Ronald

    1991-01-01

    System and terminal level specifications for an inter-satellite Optical Multiple Access (OMA) communication system are presented, as well as the resulting hardware designs for both OMA relay and OMA user terminals. The OMA relay terminal design uses a mechanical innovation which moves multiple fiber optic pickups in the focal plane, thereby providing simultaneous links with multiple OMA user terminals via a single telescope. Thus, with such a terminal on a relay satellite, multiple access service can be provided with a minimum of impact on the relay satellite.

  7. Multiple-Objective Optimal Designs for Studying the Dose Response Function and Interesting Dose Levels

    PubMed Central

    Hyun, Seung Won; Wong, Weng Kee

    2016-01-01

    We construct an optimal design to simultaneously estimate three common interesting features in a dose-finding trial with possibly different emphasis on each feature. These features are (1) the shape of the dose-response curve, (2) the median effective dose and (3) the minimum effective dose level. A main difficulty of this task is that an optimal design for a single objective may not perform well for other objectives. There are optimal designs for dual objectives in the literature but we were unable to find optimal designs for 3 or more objectives to date with a concrete application. A reason for this is that the approach for finding a dual-objective optimal design does not work well for a 3 or more multiple-objective design problem. We propose a method for finding multiple-objective optimal designs that estimate the three features with user-specified higher efficiencies for the more important objectives. We use the flexible 4-parameter logistic model to illustrate the methodology but our approach is applicable to find multiple-objective optimal designs for other types of objectives and models. We also investigate robustness properties of multiple-objective optimal designs to mis-specification in the nominal parameter values and to a variation in the optimality criterion. We also provide computer code for generating tailor made multiple-objective optimal designs. PMID:26565557

  8. Multimodel Design of Large Scale Systems with Multiple Decision Makers.

    DTIC Science & Technology

    1982-08-01

    virtue. 5- , Lead me from darkneu to light. - Lead me from death to eternal Life. ( Vedic Payer) p. I, MULTIMODEL DESIGN OF LARGE SCALE SYSTEMS WITH...guidance during the course of *: this research . He would also like to thank Professors W. R. Perkins, P. V. Kokotovic, T. Basar, and T. N. Trick for...thesis concludes with Chapter 7 where we summarize the results obtained, outline the main contributions, and indicate directions for future research . 7- I

  9. Sequential circuit design for radiation hardened multiple voltage integrated circuits

    SciTech Connect

    Clark, Lawrence T; McIver, III, John K.

    2009-11-24

    The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

  10. Optimal design of electromagnetic cloaks with multiple dielectric materials by topology optimization

    NASA Astrophysics Data System (ADS)

    Kishimoto, Naoki; Izui, Kazuhiro; Nishiwaki, Shinji; Yamada, Takayuki

    2017-05-01

    This paper presents an optimal design method for electromagnetic cloaks composed of multiple dielectric materials based on a topology optimization. To obtain optimal configurations that are perfectly free from intermediate materials, so-called grayscales, we apply a Multi-Material Level Set topology description model. The level set functions that are design variables are updated using topological derivatives that also function as design sensitivities, and we derive the topological derivatives for multiple materials. Three numerical examples demonstrate the validity of the proposed method and the advantage of using multiple materials.

  11. Signal Design for Improved Ranging Among Multiple Transceivers

    NASA Technical Reports Server (NTRS)

    Young, Lawrence; Tien, Jeffrey; Srinivasan, Jeffrey

    2004-01-01

    "Ultra-BOC" (where "BOC" signifies "binary offset carrier") is the name of an improved generic design of microwave signals to be used by a group of spacecraft flying in formation to measure ranges and bearings among themselves and to exchange telemetry needed for these measurements. Ultra-BOC could also be applied on Earth for diverse purposes -- for example, measuring relative positions of vehicles on highways for traffic-control purposes and determining the relative alignments of machines operating in mines and of construction machines and structures at construction sites. Ultra-BOC provides for rapid and robust acquisition of signals, even when signal-to-noise ratios are low. The design further provides that each spacecraft or other platform constantly strives to acquire and track the signals from the other platforms while simultaneously transmitting signals that provide full range, bearing, and telemetry service to the other platforms. In Ultra-BOC, unlike in other signal designs that have been considered for the same purposes, it is not necessary to maneuver the spacecraft or other platforms to obtain the data needed for resolving integer-carrier-cycle phase ambiguities.

  12. Design framework for spherical microphone and loudspeaker arrays in a multiple-input multiple-output system.

    PubMed

    Morgenstern, Hai; Rafaely, Boaz; Noisternig, Markus

    2017-03-01

    Spherical microphone arrays (SMAs) and spherical loudspeaker arrays (SLAs) facilitate the study of room acoustics due to the three-dimensional analysis they provide. More recently, systems that combine both arrays, referred to as multiple-input multiple-output (MIMO) systems, have been proposed due to the added spatial diversity they facilitate. The literature provides frameworks for designing SMAs and SLAs separately, including error analysis from which the operating frequency range (OFR) of an array is defined. However, such a framework does not exist for the joint design of a SMA and a SLA that comprise a MIMO system. This paper develops a design framework for MIMO systems based on a model that addresses errors and highlights the importance of a matched design. Expanding on a free-field assumption, errors are incorporated separately for each array and error bounds are defined, facilitating error analysis for the system. The dependency of the error bounds on the SLA and SMA parameters is studied and it is recommended that parameters should be chosen to assure matched OFRs of the arrays in MIMO system design. A design example is provided, demonstrating the superiority of a matched system over an unmatched system in the synthesis of directional room impulse responses.

  13. Can a Multiple-Choice Exam Discriminate Between Masters and Nonmasters of Instructional Design?

    ERIC Educational Resources Information Center

    Stepp, Sidney Leland; And Others

    1996-01-01

    Studies the statistical validation of a multiple-choice test designed to assess instructional design competency. Compares test results of instructional design professionals, graduate and nongraduate education students, and graduate and nongraduate noneducation students. Results indicate that the test accurately sorted respondents into their…

  14. REMOT: A Design for Multiple Site Remote Observing

    NASA Astrophysics Data System (ADS)

    Linde, P.; Pasian, F.; Pucillo, M.; Ponz, J. D.

    The REMOT project objective is to develop and validate a generic approach to allow remote control of scientific experiments and facilities that require real time operation and multimedia information feedback. The project is funded through the European Union Telematics initiative and is a collaboration, involving representatives from both the astro- and plasma physics communities. Standard communications infrastructure and software solutions will be used wherever possible. In the first step, requirements have been collected and analysed, resulting in a set of service definitions. These have been partly implemented to perform a set of demonstrations, showing the feasibility of the design.

  15. Design of a multiple drug delivery system directed at periodontitis.

    PubMed

    Sundararaj, Sharath C; Thomas, Mark V; Peyyala, Rebecca; Dziubla, Thomas D; Puleo, David A

    2013-11-01

    Periodontal disease is highly prevalent, with 90% of the world population affected by either periodontitis or its preceding condition, gingivitis. These conditions are caused by bacterial biofilms on teeth, which stimulate a chronic inflammatory response that leads to loss of alveolar bone and, ultimately, the tooth. Current treatment methods for periodontitis address specific parts of the disease, with no individual treatment serving as a complete therapy. The present research sought to demonstrate development of a multiple drug delivery system for stepwise treatment of different stages of periodontal disease. More specifically, multilayered films were fabricated from an association polymer comprising cellulose acetate phthalate and Pluronic F-127 to achieve sequential release of drugs. The four types of drugs used were metronidazole, ketoprofen, doxycycline, and simvastatin to eliminate infection, inhibit inflammation, prevent tissue destruction, and aid bone regeneration, respectively. Different erosion times and adjustable sequential release profiles were achieved by modifying the number of layers or by inclusion of a slower-eroding polymer layer. Analysis of antibiotic and anti-inflammatory bioactivity showed that drugs released from the devices retained 100% bioactivity. The multilayered CAPP delivery system offers a versatile approach for releasing different drugs based on the pathogenesis of periodontitis and other conditions. © 2013 Elsevier Ltd. All rights reserved.

  16. Design of a Multiple Drug Delivery System Directed at Periodontitis

    PubMed Central

    Sundararaj, Sharath C.; Thomas, Mark V.; Peyyala, Rebecca; Dziubla, Thomas D.; Puleo, David A.

    2013-01-01

    Periodontal disease is highly prevalent, with 90% of the world population affected by either periodontitis or its preceding condition, gingivitis. These conditions are caused by bacterial biofilms on teeth, which stimulate a chronic inflammatory response that leads to loss of alveolar bone and, ultimately, the tooth. Current treatment methods for periodontitis address specific parts of the disease, with no individual treatment serving as a complete therapy. The present research sought to demonstrate development of a multiple drug delivery system for stepwise treatment of different stages of periodontal disease. More specifically, multilayered films were fabricated from an association polymer comprising cellulose acetate phthalate and Pluronic F-127 to achieve sequential release of drugs. The four types of drugs used were metronidazole, ketoprofen, doxycycline, and simvastatin to eliminate infection, inhibit inflammation, prevent tissue destruction, and aid bone regeneration, respectively. Different erosion times and adjustable sequential release profiles were achieved by modifying the number of layers or by inclusion of a slower-eroding polymer layer. Analysis of antibiotic and anti-inflammatory bioactivity showed that drugs released from the devices retained 100% bioactivity. The multilayered CAPP delivery system offers a versatile approach for releasing different drugs based on the pathogenesis of periodontitis and other conditions. PMID:23948165

  17. Multiple focused EMAT designs for improved surface breaking defect characterization

    NASA Astrophysics Data System (ADS)

    Thring, C. B.; Fan, Y.; Edwards, R. S.

    2017-02-01

    Ultrasonic Rayleigh waves can be employed for the detection of surface breaking defects such as rolling contact fatigue and stress corrosion cracking. Electromagnetic Acoustic Transducers (EMATs) are well suited to this technique as they can directly generate Rayleigh waves within the sample without the requirement for wedges, and they are robust and inexpensive compared to laser ultrasonics. Three different EMAT coil types have been developed, and these are compared to assess their ability to detect and characterize small (down to 0.5 mm depth, 1 mm diameter) surface breaking defects in aluminium. These designs are: a pair of linear meander coils used in a pseudo-pulse-echo mode, a pair of focused meander coils also used in pseudo-pulse-echo mode, and a pair of focused racetrack coils used in pitch-catch mode. The linear meander coils are able to detect most of the defects tested, but have a much lower signal to noise ratio and give limited sizing information. The focused meander coils and the focused racetrack coils can detect all defects tested, but have the advantage that they can also characterize the defect sizes on the sample surface, and have a stronger sensitivity at their focal point. Measurements using all three EMAT designs are presented and compared for high resolution imaging of surface-breaking defects.

  18. Design Optimization for Multiple Management Period Groundwater Remediation

    NASA Astrophysics Data System (ADS)

    Rizzo, Donna M.; Dougherty, David E.

    1996-08-01

    A technique for obtaining a (nearly) optimal scheme using multiple management periods has been developed. The method has been developed for very large scale combinatorial optimization problems. Simulated annealing has been extended to this problem. An importance function is developed to accelerate the search for good solutions. These tools have been applied to groundwater remediation problems at Lawrence Livermore National Laboratory (LLNL). A deterministic site-specific engineering-type flow and transport model (based on the public domain code SUTRA) is combined with the heuristic optimization technique. The objective is to obtain the time-varying optimal locations of the remediation wells that will reduce concentration levels of volatile organic chemicals in groundwater below a given threshold at specified areas on the LLNL site within a certain time frame and subject to a variety of realistic complicating factors. The cost function incorporates construction costs, operation and maintenance costs for injection and extraction wells, costs associated with piping and treatment facilities, and a performance penalty for well configurations that generate flow and transport simulations that exceed maximum concentration levels at specified locations. The resulting application reported here comprises a huge optimization problem. The importance function detailed in this paper has led to rapid convergence to solutions. The performance penalty allows different goals to be imposed on different geographical regions of the site; in this example, short-term off-site plume containment and long-term on-site cleanup are imposed. The performance of the optimization scheme and the effects of various trade-offs in management objectives are explored through examples using the LLNL site.

  19. Development of optimal design theory for series multiple tuned mass dampers considering stroke and multiple structural modes

    NASA Astrophysics Data System (ADS)

    Wang, J. F.; Lin, C. C.

    2016-09-01

    A tuned mass damper (TMD) system generates structural control forces through large motions of mass units. Therefore, it may not be functional if the stroke capacity of its spring and damper components are insufficient. This paper focuses on a novel mass-damper system, the series multiple tuned mass damper (SMTMD) system, which consists of multiple interconnected TMDs, of which only the first is connected to the primary structure. The main purpose of this paper is to compare the control effectiveness and TMD stroke of SMTMDs with those of a conventional TMD device. In addition, the ability of the studied SMTMD to suppress multiple structural modes is also investigated. First, the optimal design theory for an SMTMD installed on an arbitrary floor of a multi-storey building is developed. To optimize the SMTMD parameters, two performance indices are established by combining multiple modal responses of the primary structure. The developed theory is demonstrated analytically by using a three-story building. The results show that the SMTMD with a higher number of TMD units places lower demands on the TMD stroke and is more adaptive in controlling multiple structural modes of the primary structure.

  20. Optimal design of structures with multiple design variables per group and multiple loading conditions on the personal computer

    NASA Technical Reports Server (NTRS)

    Nguyen, D. T.; Rogers, J. L., Jr.

    1986-01-01

    A finite element based programming system for minimum weight design of a truss-type structure subjected to displacement, stress, and lower and upper bounds on design variables is presented. The programming system consists of a number of independent processors, each performing a specific task. These processors, however, are interfaced through a well-organized data base, thus making the tasks of modifying, updating, or expanding the programming system much easier in a friendly environment provided by many inexpensive personal computers. The proposed software can be viewed as an important step in achieving a 'dummy' finite element for optimization. The programming system has been implemented on both large and small computers (such as VAX, CYBER, IBM-PC, and APPLE) although the focus is on the latter. Examples are presented to demonstrate the capabilities of the code. The present programming system can be used stand-alone or as part of the multilevel decomposition procedure to obtain optimum design for very large scale structural systems. Furthermore, other related research areas such as developing optimization algorithms (or in the larger level: a structural synthesis program) for future trends in using parallel computers may also benefit from this study.

  1. Optimal design of structures with multiple design variables per group and multiple loading conditions on the personal computer

    NASA Technical Reports Server (NTRS)

    Nguyen, D. T.; Rogers, J. L., Jr.

    1986-01-01

    A finite element based programming system for minimum weight design of a truss-type structure subjected to displacement, stress, and lower and upper bounds on design variables is presented. The programming system consists of a number of independent processors, each performing a specific task. These processors, however, are interfaced through a well-organized data base, thus making the tasks of modifying, updating, or expanding the programming system much easier in a friendly environment provided by many inexpensive personal computers. The proposed software can be viewed as an important step in achieving a 'dummy' finite element for optimization. The programming system has been implemented on both large and small computers (such as VAX, CYBER, IBM-PC, and APPLE) although the focus is on the latter. Examples are presented to demonstrate the capabilities of the code. The present programming system can be used stand-alone or as part of the multilevel decomposition procedure to obtain optimum design for very large scale structural systems. Furthermore, other related research areas such as developing optimization algorithms (or in the larger level: a structural synthesis program) for future trends in using parallel computers may also benefit from this study.

  2. Cross layer optimization for cloud-based radio over optical fiber networks

    NASA Astrophysics Data System (ADS)

    Shao, Sujie; Guo, Shaoyong; Qiu, Xuesong; Yang, Hui; Meng, Luoming

    2016-07-01

    To adapt the 5G communication, the cloud radio access network is a paradigm introduced by operators which aggregates all base stations computational resources into a cloud BBU pool. The interaction between RRH and BBU or resource schedule among BBUs in cloud have become more frequent and complex with the development of system scale and user requirement. It can promote the networking demand among RRHs and BBUs, and force to form elastic optical fiber switching and networking. In such network, multiple stratum resources of radio, optical and BBU processing unit have interweaved with each other. In this paper, we propose a novel multiple stratum optimization (MSO) architecture for cloud-based radio over optical fiber networks (C-RoFN) with software defined networking. Additionally, a global evaluation strategy (GES) is introduced in the proposed architecture. MSO can enhance the responsiveness to end-to-end user demands and globally optimize radio frequency, optical spectrum and BBU processing resources effectively to maximize radio coverage. The feasibility and efficiency of the proposed architecture with GES strategy are experimentally verified on OpenFlow-enabled testbed in terms of resource occupation and path provisioning latency.

  3. Multiple-baseline design in instructional research: pitfalls of measurement and procedural advantages.

    PubMed

    Cuvo, A J

    1979-11-01

    The multiple-baseline design has utility for evaluating the instructional programs used with mentally retarded persons; however, there are several pitfalls of measurement that may be encountered in using this design. Subjects' performance may be inadvertently altered by (a) repeated testing during baseline, (b) a procedural contrast between training and testing, and (c) inaccurate generalization during testing. Procedures to mitigate the effects of these problems were recommended. The pitfalls may arise in part because of the direct interpersonal nature of measuring the dependent variable in instructional research. Also, the pitfalls are not inherent in the multiple-baseline design per se but are issues of measurement that may occur in other designs as well. Finally, the advantage of using the multiple-baseline design to study covariation of responding was highlighted.

  4. Randomization tests for multiple-baseline designs: an extension of the SCRT-R package.

    PubMed

    Bulté, Isis; Onghena, Patrick

    2009-05-01

    Multiple-baseline designs are an extension of the basic single-case AB phase designs, in which several of those AB designs are implemented simultaneously to different persons, behaviors, or settings, and the intervention is introduced in a staggered way to the different units. These designs are well-suited for research in the behavioral sciences. We discuss the advantages and limitations for valid inferences, and suggest a statistical technique--randomization tests--for use with multiple-baseline data, to complement visual analysis. In addition, we provide an extension of our SCRT-R package (which already contained means for conducting randomization tests on single-case phase and alternation designs), for multiple-baseline AB data.

  5. Unmanned Multiple Exploratory Probe System (MEPS) for Mars observation. Volume 1: Trade analysis and design

    NASA Technical Reports Server (NTRS)

    Adams, Daniel E.; Crumbly, Christopher M.; Delp, Steve E.; Guidry, Michelle A.; Lisano, Michael E.; Packard, James D.; Striepe, Scott A.

    1988-01-01

    This report presents the unmanned Multiple Exploratory Probe Systems (MEPS), a space vehicle designed to observe the planet Mars in preparation for manned missions. The options considered for each major element are presented as a trade analysis, and the final vehicle design is defined.

  6. Experimental Control and Threats to Internal Validity of Concurrent and Nonconcurrent Multiple Baseline Designs

    ERIC Educational Resources Information Center

    Christ, Theodore J.

    2007-01-01

    Single-case research designs are often applied within school psychology. This article provides a critical review of the scientific merit of both concurrent and nonconcurrent multiple baseline (MB) designs, relative to their capacity to assess threats of internal validity and establish experimental control. Distinctions are established between AB…

  7. Experimental Control and Threats to Internal Validity of Concurrent and Nonconcurrent Multiple Baseline Designs

    ERIC Educational Resources Information Center

    Christ, Theodore J.

    2007-01-01

    Single-case research designs are often applied within school psychology. This article provides a critical review of the scientific merit of both concurrent and nonconcurrent multiple baseline (MB) designs, relative to their capacity to assess threats of internal validity and establish experimental control. Distinctions are established between AB…

  8. Validation of the MCNPX-PoliMi Code to Design a Fast-Neutron Multiplicity Counter

    SciTech Connect

    J. L. Dolan; A. C. Kaplan; M. Flaska; S. A. Pozzi; D. L. Chichester

    2012-07-01

    Many safeguards measurement systems used at nuclear facilities, both domestically and internationally, rely on He-3 detectors and well established mathematical equations to interpret coincidence and multiplicity-type measurements for verifying quantities of special nuclear material. Due to resource shortages alternatives to these existing He-3 based systems are being sought. Work is also underway to broaden the capabilities of these types of measurement systems in order to improve current multiplicity analysis techniques. As a part of a Material Protection, Accounting, and Control Technology (MPACT) project within the U.S. Department of Energy's Fuel Cycle Technology Program we are designing a fast-neutron multiplicity counter with organic liquid scintillators to quantify important quantities such as plutonium mass. We are also examining the potential benefits of using fast-neutron detectors for multiplicity analysis of advanced fuels in comparison with He-3 detectors and testing the performance of such designs. The designs are being developed and optimized using the MCNPX-PoliMi transport code to study detector response. In the full paper, we will discuss validation measurements used to justify the use of the MCNPX-PoliMi code paired with the MPPost multiplicity routine to design a fast neutron multiplicity counter with liquid scintillators. This multiplicity counter will be designed with the end goal of safeguarding advanced nuclear fuels. With improved timing qualities associated with liquid scintillation detectors, we can design a system that is less limited by nuclear materials of high activities. Initial testing of the designed system with nuclear fuels will take place at Idaho National Laboratory in a later stage of this collaboration.

  9. Cross-layer optimization of video streaming in single-hop wireless networks

    NASA Astrophysics Data System (ADS)

    Hsu, Cheng-Hsin; Hefeeda, Mohamed

    2009-01-01

    Video streaming over wireless networks is getting very popular because of the high bandwidth and the support of quality of service offered by recent wireless standards, such as IEEE 802.11e. We consider optimizing the quality of video streaming in single-hop wireless networks that are composed of multiple wireless stations. Our optimization problem controls parameters in different layers to optimally allocate the wireless network resources among all stations. We address this problem in two steps. First, we formulate an abstract optimization problem for video streaming in single-hop wireless networks in general. This formulation exposes the important interaction between parameters belonging to different layers in the network stack. Then, we instantiate and solve the general problem for the recent IEEE 802.11e WLANs, which support prioritized traffic classes. We show how the calculated optimal solutions can efficiently be implemented in the distributed mode of the IEEE 802.11e standard. We evaluate our proposed solution using extensive simulations in the OPNET simulator, which captures most features of realistic wireless networks. In addition, to show the practicability of our solution, we have implemented it in the driver of an off-the-shelf wireless adapter that complies with the IEEE 802.11e standard. Our experimental and simulation results show that significant quality improvement in video streams can be achieved using our solution, without incurring any significant communication or computational overhead.

  10. The Europa Mission: Multiple Europa Flyby Trajectory Design Trades and Challenges

    NASA Technical Reports Server (NTRS)

    Lam, Try; Arrieta-Camacho, Juan J.; Buffington, Brent B.

    2015-01-01

    With potential sources of water, energy and other chemicals essential for life, Europa is a top candidate for finding current life in our Solar System outside of Earth. This paper describes the current trajectory design concept for a multiple Europa flyby mission and discusses several trajectory design challenges. The candidate reference trajectory utilizes multiple Europa flybys while around Jupiter to enable near global coverage of Europa while balancing science requirements, radiation dose, propellant usage, and flight time. Trajectory design trades and robustness are also discussed.

  11. Greene SCPrimer: a rapid comprehensive tool for designing degenerate primers from multiple sequence alignments

    PubMed Central

    Jabado, Omar J.; Palacios, Gustavo; Kapoor, Vishal; Hui, Jeffrey; Renwick, Neil; Zhai, Junhui; Briese, Thomas; Lipkin, W. Ian

    2006-01-01

    Polymerase chain reaction (PCR) is widely applied in clinical and environmental microbiology. Primer design is key to the development of successful assays and is often performed manually by using multiple nucleic acid alignments. Few public software tools exist that allow comprehensive design of degenerate primers for large groups of related targets based on complex multiple sequence alignments. Here we present a method for designing such primers based on tree building followed by application of a set covering algorithm, and demonstrate its utility in compiling Multiplex PCR primer panels for detection and differentiation of viral pathogens. PMID:17135211

  12. Robust design of multiple-input multiple-output radar waveform covariance matrix in the presence of clutter

    NASA Astrophysics Data System (ADS)

    Guo, Rongyan; Wang, Hongyan

    2016-07-01

    In this work, the issue of robust waveform optimization is addressed in the presence of clutter to improve the worst-case estimation accuracy for collocated multiple-input multiple-output (MIMO) radar. Robust design is necessary due to the fact that waveform design may be sensitive to uncertainties in the initial parameter estimates. Following the min-max approach, the robust waveform covariance matrix design is formulated here on the basis of Cramér-Rao Bound to ease this sensitivity systematically for improving the worst-case accuracy. To tackle the resultant complicated and nonlinear problem, a new diagonal loading (DL)-based iterative approach is developed, in which the inner optimization problem can first be decomposed to some independent subproblems by using the Hadamard's inequality, and then these subproblems can be reformulated into convex issues by using DL method, as well as the outer optimization problem can also be relaxed to a convex issue by translating the nonlinear function into a linear one, and, hence, both of them can be solved very effectively. An optimal solution to the original problem can be obtained via the least-squares fitting of the solution acquired by the iterative approach. Numerical simulations show the efficiency of the proposed method.

  13. Cross-Layer Self-Adaptive/Self-Aware System Software for Exascale Systems

    SciTech Connect

    Gioiosa, Roberto; Kestor, Gokcen; Kerbyson, Darren J.; Hoisie, Adolfy

    2014-10-22

    The extreme level of parallelism coupled with the limited available power budget expected in the exascale era brings unprecedented challenges that demand optimization of performance, power and resiliency in unison. Scalability on such systems is of paramount importance, while power and reliability issues may change the execution environment in which a parallel application runs. To solve these challenges exascale systems will require an introspective system software that combines system and application observations across all system stack layers with online feedback and adaptation mechanisms. In this paper we propose the design of a novel self-aware, self-adaptive system software in which a kernel-level Monitor, which continuously inspects the evolution of the target system through observation of Sensors, is combined with a user-level Controller, which reacts to changes in the execution environment, explores opportunities to increase performance, save power and adapts applications to new execution scenarios. We show that the monitoring system accurately monitors the evolution of parallel applications with a runtime overhead below 1-2%. As a test case, we design and implement a user-runtime system that aims at optimizing application’s performance and system power consumption on complex hierarchical architectures. Our results show that our adaptive system reaches 98% of performance efficiency of manually-tuned applications.

  14. Spread Spectrum Visual Sensor Network Resource Management Using an End-to-End Cross-Layer Design

    DTIC Science & Technology

    2011-02-01

    APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. PA Case Number: WPAFB-08- 3693 DATE CLEARED: 11 JUNE 2008 13. SUPPLEMENTARY NOTES © 2011 IEEE...Elizabeth S. Bentley, Lisimachos P. Kondi, Member, IEEE, John D . Matyjas, Michael J. Medley, Senior Member, IEEE, and Bruce W. Suter Abstract—In this...was Dr. Qian Zhang. E. S. Bentley, J. D . Matyjas, M. J. Medley, and B. W. Suter are with the Air Force Research Laboratory, Rome, NY 13441 USA. L. P

  15. Design of Intelligent Cross-Layer Routing Protocols for Airborne Wireless Networks Under Dynamic Spectrum Access Paradigm

    DTIC Science & Technology

    2011-05-01

    manet-aodv-11.txt 107 17. D. Johnson, D. A. Maltz, and J. Broch , “The Dynamic Source Routing Protocol for Mobile Ad Hoc Networks,” IETF Internet...multipath distance vector routing,” Wireless Communications And Mobile Computing, vol. 6, pp. 969–988, 2006. 51. J. Broch , D. Maltz, D. Johnson, Y. Hu...wireless networks,” Proc. INFOCOM’97, pp. 1405–1413, April 1997. 55. J. Broch , D. Johnson, and D.Maltz, “The dynamic source routing protocol for mobile ad

  16. Bilevel formulation of a policy design problem considering multiple objectives and incomplete preferences

    NASA Astrophysics Data System (ADS)

    Hawthorne, Bryant; Panchal, Jitesh H.

    2014-07-01

    A bilevel optimization formulation of policy design problems considering multiple objectives and incomplete preferences of the stakeholders is presented. The formulation is presented for Feed-in-Tariff (FIT) policy design for decentralized energy infrastructure. The upper-level problem is the policy designer's problem and the lower-level problem is a Nash equilibrium problem resulting from market interactions. The policy designer has two objectives: maximizing the quantity of energy generated and minimizing policy cost. The stakeholders decide on quantities while maximizing net present value and minimizing capital investment. The Nash equilibrium problem in the presence of incomplete preferences is formulated as a stochastic linear complementarity problem and solved using expected value formulation, expected residual minimization formulation, and the Monte Carlo technique. The primary contributions in this article are the mathematical formulation of the FIT policy, the extension of computational policy design problems to multiple objectives, and the consideration of incomplete preferences of stakeholders for policy design problems.

  17. The UCLA Design Diversity Experiment (DEDIX) system: A distributed testbed for multiple-version software

    NASA Technical Reports Server (NTRS)

    Avizienis, A.; Gunningberg, P.; Kelly, J. P. J.; Strigini, L.; Traverse, P. J.; Tso, K. S.; Voges, U.

    1986-01-01

    To establish a long-term research facility for experimental investigations of design diversity as a means of achieving fault-tolerant systems, a distributed testbed for multiple-version software was designed. It is part of a local network, which utilizes the Locus distributed operating system to operate a set of 20 VAX 11/750 computers. It is used in experiments to measure the efficacy of design diversity and to investigate reliability increases under large-scale, controlled experimental conditions.

  18. WIFI and WIMAX Optimization Design of Transmission and Application

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Wu, Xian Li

    WIFI (Wireless Fidelity) and WIMAX (Worldwide Interoperability for Microwave Access) using OFDM / OFDMA, MIMO technology to achieve speeds in a unified platform for data, voice, high-definition video and other wireless transmission, For many industries of wireless communication may be short, very considerable practical prospect. This paper focuses on WIFI and WIMAX transmission optimization design, including space-time coding (abbreviated as: STC), multiple-access control (MAC) protocol of the mathematical model; traffic channel terminal mobility cross-layer design to achieve multi-layer co-optimization, improve the WIFI and WIMAX, transmission efficiency, making WIFI and WIMAX transmission are more reasonable.

  19. Design of Experiments with Multiple Independent Variables: A Resource Management Perspective on Complete and Reduced Factorial Designs

    ERIC Educational Resources Information Center

    Collins, Linda M.; Dziak, John J.; Li, Runze

    2009-01-01

    An investigator who plans to conduct an experiment with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy.…

  20. Development of Stability/Robustness Considerations for Control System Design with Multiple Input/Multiple Output Plants

    DTIC Science & Technology

    1988-06-10

    multiple input / multiple output ( MIMO ...Unstable.80 Ut NOTATION MIMO Multiple Input / Multiple Output SISO Single Input /Single Output A,B,C Nominal Plant Matrices Acl Nominal Plant Closed...giving way to plants with multiple inputs and multiple outputs ( MIMO ) as technology races ahead. Extremely advanced systems such as the Navy’s

  1. Multi-objective optimization for RNA design with multiple target secondary structures.

    PubMed

    Taneda, Akito

    2015-09-03

    RNAs are attractive molecules as the biological parts for synthetic biology. In particular, the ability of conformational changes, which can be encoded in designer RNAs, enables us to create multistable molecular switches that function in biological circuits. Although various algorithms for designing such RNA switches have been proposed, the previous algorithms optimize the RNA sequences against the weighted sum of objective functions, where empirical weights among objective functions are used. In addition, an RNA design algorithm for multiple pseudoknot targets is currently not available. We developed a novel computational tool for automatically designing RNA sequences which fold into multiple target secondary structures. Our algorithm designs RNA sequences based on multi-objective genetic algorithm, by which we can explore the RNA sequences having good objective function values without empirical weight parameters among the objective functions. Our algorithm has great flexibility by virtue of this weight-free nature. We benchmarked our multi-target RNA design algorithm with the datasets of two, three, and four target structures and found that our algorithm shows better or comparable design performances compared with the previous algorithms, RNAdesign and Frnakenstein. In addition to the benchmarks with pseudoknot-free datasets, we benchmarked MODENA with two-target pseudoknot datasets and found that MODENA can design the RNAs which have the target pseudoknotted secondary structures whose free energies are close to the lowest free energy. Moreover, we applied our algorithm to a ribozyme-based ON-switch which takes a ribozyme-inactive secondary structure when the theophylline aptamer structure is assumed. Currently, MODENA is the only RNA design software which can be applied to multiple pseudoknot targets. Successful design results for the multiple targets and an RNA device indicate usefulness of our multi-objective RNA design algorithm.

  2. Evaluation of cabin design based on the method of multiple attribute group decision-making

    NASA Astrophysics Data System (ADS)

    Li, Xiaowen; Lv, Linlin; Li, Ping

    2013-07-01

    New century, cabin design has become an important factor affecting the compact capability of modern naval vessels. Traditional cabin design, based on naval rules and designer's subjective feeling and experience, holds that weapons and equipments are more important than habitability. So crew's satisfaction is not high to ships designed by traditional methods. In order to solve this problem, the method of multiple attribute group decision-making was proposed to evaluate the cabin design projects. This method considered many factors affecting cabin design, established a target system, quantified fuzzy factors in cabin design, analyzed the need of crews and gave a reasonable evaluation on cabin design projects. Finally, an illustrative example analysis validates the effectiveness and reliability of this method.

  3. Optimum design of a fuel-cell powertrain based on multiple design criteria

    NASA Astrophysics Data System (ADS)

    Sarioglu, Ismail Levent; Czapnik, Bartosch; Bostanci, Emine; Klein, Olaf P.; Schröder, Hendrik; Küçükay, Ferit

    2014-11-01

    As the number of fuel-cell vehicles on the roads increase, the vehicle designs are gaining more importance. Clearly, one major topic in this field is the optimization of powertrain designs. In this design process, the aim of the car manufacturers is to meet the expectations of the potential customer best, while creating a sustainable product. However, due to several trade-offs in the design, it would be non-realistic to expect a single solution that fulfills all design objectives. Therefore, a systematical approach, which includes a trade-off analysis and evaluation methods for this multiobjective design problem, is required. In this paper, a suitable methodology is presented and applied in a case study, where an optimum powertrain design for a typical European long-range passenger car is sought. Simulation-aided powertrain models and scalable component models are used to increase the accuracy of the design process. Furthermore, various visual and quantitative evaluation techniques are applied in order to support the decision making process.

  4. Design of Experiments with Multiple Independent Variables: A Resource Management Perspective on Complete and Reduced Factorial Designs

    PubMed Central

    Collins, Linda M.; Dziak, John J.; Li, Runze

    2009-01-01

    An investigator who plans to conduct experiments with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy. Considerations in making design decisions include whether research questions are framed as main effects or simple effects; whether and which effects are aliased (confounded) in a particular design; the number of experimental conditions that must be implemented in a particular design and the number of experimental subjects the design requires to maintain the desired level of statistical power; and the costs associated with implementing experimental conditions and obtaining experimental subjects. In this article four design options are compared: complete factorial, individual experiments, single factor, and fractional factorial designs. Complete and fractional factorial designs and single factor designs are generally more economical than conducting individual experiments on each factor. Although relatively unfamiliar to behavioral scientists, fractional factorial designs merit serious consideration because of their economy and versatility. PMID:19719358

  5. Design and analysis of multiple diseases genome-wide association studies without controls.

    PubMed

    Chen, Zhongxue; Huang, Hanwen; Ng, Hon Keung Tony

    2012-11-15

    In genome-wide association studies (GWAS), multiple diseases with shared controls is one of the case-control study designs. If data obtained from these studies are appropriately analyzed, this design can have several advantages such as improving statistical power in detecting associations and reducing the time and cost in the data collection process. In this paper, we propose a study design for GWAS which involves multiple diseases but without controls. We also propose corresponding statistical data analysis strategy for GWAS with multiple diseases but no controls. Through a simulation study, we show that the statistical association test with the proposed study design is more powerful than the test with single disease sharing common controls, and it has comparable power to the overall test based on the whole dataset including the controls. We also apply the proposed method to a real GWAS dataset to illustrate the methodologies and the advantages of the proposed design. Some possible limitations of this study design and testing method and their solutions are also discussed. Our findings indicate that the proposed study design and statistical analysis strategy could be more efficient than the usual case-control GWAS as well as those with shared controls. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Correlation filter design for classification of road sign by multiple optical correlators

    NASA Astrophysics Data System (ADS)

    Taniguchi, Masaki; Mokuno, Yoshiaki; Kintaka, Kenji; Matsuoka, Katsunori

    1999-10-01

    We propose a new technique of correlation filter design for optical correlator. For detection and classification of complex patterns, ability of single optical correlator is not enough. To achieve high performance of classification, a multiple correlator is suitable in respect of flexibility in correlation filter design. We attempt to design a set of correlation filters for use in multiple optical correlators. As the target, we select road signs. In real scene, the scale and aspect ratio of road sign are dependent on the distance and angle of observation. In addition, many kinds of signs are used. Therefore the correlation filter set has to be designed as to have distortion invariance to adapt to the change of aspect and the variation of road signs. We apply the technique of multiple-object correlation filter, such as the synthetic discriminant function, to the design of correlation filter set, in order to obtain the necessary invariance. We calculate 180 filters in order to detect and classify 15 kinds of Japanese road signs in real scene. Computer simulation result shows that the combination of multiple optical correlator with the correlation filter set can indicate high performance of pattern detection and classification.

  7. Neural network and multiple linear regression to predict school children dimensions for ergonomic school furniture design.

    PubMed

    Agha, Salah R; Alnahhal, Mohammed J

    2012-11-01

    The current study investigates the possibility of obtaining the anthropometric dimensions, critical to school furniture design, without measuring all of them. The study first selects some anthropometric dimensions that are easy to measure. Two methods are then used to check if these easy-to-measure dimensions can predict the dimensions critical to the furniture design. These methods are multiple linear regression and neural networks. Each dimension that is deemed necessary to ergonomically design school furniture is expressed as a function of some other measured anthropometric dimensions. Results show that out of the five dimensions needed for chair design, four can be related to other dimensions that can be measured while children are standing. Therefore, the method suggested here would definitely save time and effort and avoid the difficulty of dealing with students while measuring these dimensions. In general, it was found that neural networks perform better than multiple linear regression in the current study.

  8. Design of experiments with multiple independent variables: a resource management perspective on complete and reduced factorial designs.

    PubMed

    Collins, Linda M; Dziak, John J; Li, Runze

    2009-09-01

    An investigator who plans to conduct an experiment with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy. Considerations in making design decisions include whether research questions are framed as main effects or simple effects; whether and which effects are aliased (confounded) in a particular design; the number of experimental conditions that must be implemented in a particular design and the number of experimental subjects the design requires to maintain the desired level of statistical power; and the costs associated with implementing experimental conditions and obtaining experimental subjects. In this article 4 design options are compared: complete factorial, individual experiments, single factor, and fractional factorial. Complete and fractional factorial designs and single-factor designs are generally more economical than conducting individual experiments on each factor. Although relatively unfamiliar to behavioral scientists, fractional factorial designs merit serious consideration because of their economy and versatility.

  9. RegRand: statistical software for the multiple-baseline design.

    PubMed

    Koehler, M J; Levin, J R

    2000-05-01

    RegRand (Version 1.0) is Macintosh-based software that enables a researcher to conduct a non-parametric statistical analysis of the data from Koehler and Levin's (1998) recently described regulated randomization single-case multiple-baseline design. Regulated randomization design and analysis principles are reviewed in relation to an educational research application and a step-by-step illustration of them in relation to the RegRand program is presented.

  10. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

    PubMed

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-09-18

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

  11. In situ neutralisation of uncarbonated bauxite residue mud by cross layer leaching with carbonated bauxite residue mud.

    PubMed

    Santini, T C; Hinz, C; Rate, A W; Carter, C M; Gilkes, R J

    2011-10-30

    Unameliorated residue mud from the Bayer process generates highly alkaline leachates (pH ca. 13) after deposition in storage areas. Pre-deposition treatment of bauxite residue mud (BRM) with CO(2) gas (carbonation) lowers leachate pH to ca. 10.5. Laboratory scale leaching columns were used to investigate the potential for in situ pH reduction in existing uncarbonated BRM deposits through exposure to carbonated mud leachate. Leachates from uncarbonated and carbonated residues in single and dual-layer column configurations were analysed for pH, electrical conductivity, carbonate and bicarbonate content, and element concentrations. Air-dried solids were analysed by X-ray diffraction before and after leaching. Cross layer leaching lowers leachate pH from uncarbonated BRM. Leachate pH was significantly lower in dual layer and carbonated residue than in uncarbonated residue between one and 400 pore volumes leached. Carbonated residue porewater as well as dawsonite and calcite dissolution were identified as sources of (bi-)carbonate. Leachate concentrations of As, Cr, Cu, Ga and La were immediately reduced in dual layer treatments compared with uncarbonated residue. No element analysed exhibited a significantly higher leachate concentration in dual layer treatments than the highest observed concentration in single layer treatments. The implementation of dual layer leaching in the field therefore presents an opportunity to improve leachate quality from existing uncarbonated residue deposits and justifies further testing at field scale. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

    PubMed Central

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-01-01

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

  13. Supporting affect regulation in children with multiple disabilities during psychotherapy: a multiple case design study of therapeutic attachment.

    PubMed

    Schuengel, C; Sterkenburg, P S; Jeczynski, P; Janssen, C G C; Jongbloed, G

    2009-04-01

    In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist stimulating therapeutic attachment, alternating with a control therapist providing positive personal attention only. In the 2nd phase, both therapists applied behavior therapy. Clients sought more proximity to the experimental therapist compared with the control therapist. Psychophysiological arousal (respiratory sinus arrhythmia and pre-ejection period) was lower when the experimental therapist applied behavior modification than when the control therapist did. Despite prolonged social deprivation, the attachment behavioral system appeared responsive to stimulation. The effects on affect regulation may explain the synergy between psychotherapy based on interpersonal and behavior modification approaches.

  14. Estimation of Reliability for Multiple-Component Measuring Instruments in Hierarchical Designs

    ERIC Educational Resources Information Center

    Raykov, Tenko; du Toit, Stephen H. C.

    2005-01-01

    A method for estimation of reliability for multiple-component measuring instruments with clustered data is outlined. The approach is applicable with hierarchical designs where individuals are nested within higher order units and exhibit possibly related performance on components of a scale of interest. The procedure is developed within the…

  15. PC-based Multiple Information System Interface (PC/MISI) detailed design and implementation plan

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor); Hall, Philip P.

    1985-01-01

    The design plan for the personal computer multiple information system interface (PC/MISI) project is discussed. The document is intended to be used as a blueprint for the implementation of the system. Each component is described in the detail necessary to allow programmers to implement the system. A description of the system data flow and system file structures is given.

  16. Multiple Precision Arithmetic Design with an Implementation on the UNIVAC 1108.

    DTIC Science & Technology

    arichmetic unit which is described operates on multiple precision numbers in a manner similar to existing floating point capabilities and offers additional...facilities not currently available in hardware. Many of the conclusions are applicable to hardware floating point arithmetic design. (Author)

  17. Radiological risk evaluation for risk-based design criteria of the multiple canister overpack packaging

    SciTech Connect

    Green, J.R., Westinghouse Hanford

    1996-07-18

    The Multiple Canister Overpack (MCO) cask will be used in the transportation of irradiated nuclear fuel from the K Basins to a Canister Storage Building. This report presents the radiological risk evaluation, which is used in the development of the design criteria for the MCO cask. The radiological risk evaluation ensures compliance with the onsite transportation safety program.

  18. Obtaining Paired Comparisons Data from Multiple Rank Orders Using Partially Balanced Incomplete Block Designs

    ERIC Educational Resources Information Center

    Straton, Ralph G.

    1975-01-01

    Complete paired comparisons data was obtained by use of multiple rank order (MRO) in the context of gathering rank order preferences of grade six students, their parents, and teachers for instructional objectives. Partially balanced incomplete block designs with two associate classes were used in the MRO instruments instead of the usual balanced…

  19. PC-based Multiple Information System Interface (PC/MISI) design plan

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor); Hall, Philip P.

    1985-01-01

    The general design plan for the implementation of a common user interface to multiple remote information systems within a microcomputer-based environment is presented. The intent is to provide a framework for the development of detailed specifications which will be used as guidelines for the actual development of the system.

  20. The Design of Lessons Using Mathematics Analysis Software to Support Multiple Representations in Secondary School Mathematics

    ERIC Educational Resources Information Center

    Pierce, Robyn; Stacey, Kaye; Wander, Roger; Ball, Lynda

    2011-01-01

    Current technologies incorporating sophisticated mathematical analysis software (calculation, graphing, dynamic geometry, tables, and more) provide easy access to multiple representations of mathematical problems. Realising the affordances of such technology for students' learning requires carefully designed lessons. This paper reports on design…

  1. A novel ring type ultrasonic motor with multiple wavenumbers: design, fabrication and characterization

    NASA Astrophysics Data System (ADS)

    Duan, W. H.; Quek, S. T.; Wang, Q.

    2009-12-01

    A novel ring type traveling wave ultrasonic motor (USM) with multiple wavenumbers has been designed, fabricated and characterized. This multiple wavenumber operation is realized by means of a new electrode configuration of the piezoelectric element. The experimental and numerical performance results for the multiple wavenumbers show that USM with multiple wavenumbers significantly outperform the single wavenumber motor as regards the range of speed and torque output. This novel implementation of the traveling wave motor also offers extra control for stable operation of USM. The performances of the control variables, the wavenumber and the amplitude, are compared to show their advantages and disadvantages. The speed control range for the wavenumber is larger than that for amplitude control; wavenumber control has better stability at low speed while amplitude control can work continuously with less wear. Hybrid control using both methods may result in better performance of USM.

  2. Optimal design of compact and connected nature reserves for multiple species.

    PubMed

    Wang, Yicheng; Önal, Hayri

    2016-04-01

    When designing a conservation reserve system for multiple species, spatial attributes of the reserves must be taken into account at species level. The existing optimal reserve design literature considers either one spatial attribute or when multiple attributes are considered the analysis is restricted only to one species. We built a linear integer programing model that incorporates compactness and connectivity of the landscape reserved for multiple species. The model identifies multiple reserves that each serve a subset of target species with a specified coverage probability threshold to ensure the species' long-term survival in the reserve, and each target species is covered (protected) with another probability threshold at the reserve system level. We modeled compactness by minimizing the total distance between selected sites and central sites, and we modeled connectivity of a selected site to its designated central site by selecting at least one of its adjacent sites that has a nearer distance to the central site. We considered structural distance and functional distances that incorporated site quality between sites. We tested the model using randomly generated data on 2 species, one ground species that required structural connectivity and the other an avian species that required functional connectivity. We applied the model to 10 bird species listed as endangered by the state of Illinois (U.S.A.). Spatial coherence and selection cost of the reserves differed substantially depending on the weights assigned to these 2 criteria. The model can be used to design a reserve system for multiple species, especially species whose habitats are far apart in which case multiple disjunct but compact and connected reserves are advantageous. The model can be modified to increase or decrease the distance between reserves to reduce or promote population connectivity. © 2015 Society for Conservation Biology.

  3. A design study to develop young children's understanding of multiplication and division

    NASA Astrophysics Data System (ADS)

    Bicknell, Brenda; Young-Loveridge, Jenny; Nguyen, Nhung

    2016-12-01

    This design study investigated the use of multiplication and division problems to help 5-year-old children develop an early understanding of multiplication and division. One teacher and her class of 15 5-year-old children were involved in a collaborative partnership with the researchers. The design study was conducted over two 4-week periods in May-June and October-November. The focus in this article is on three key aspects of classroom teaching: instructional tasks, the use of representations, and discourse, including the mathematics register. Results from selected pre- and post-assessment tasks within a diagnostic interview showed that there were improvements in addition and subtraction as well as multiplication and division, even though the teaching had used multiplication and division problems. Students made progress on all four operational domains, with effect sizes ranging from approximately two thirds of a standard deviation to 2 standard deviations. Most of the improvement in students' number strategies was in moving from `counting all' to `counting on' and `skip counting'. The findings challenge the idea that learning experiences in addition and subtraction should precede those in multiplication and division as suggested in some curriculum documents.

  4. Design and analysis of non-pharmacological treatment trials with multiple therapists per patient.

    PubMed

    Roberts, Chris; Walwyn, Rebecca

    2013-01-15

    In trials of physical and talking therapies, nesting of patients within therapists has statistical implications analogous to those of cluster randomised trials. Nevertheless, the clustering effect may be more complex, as it interacts with treatment. For some therapies, individual patients may receive care from multiple therapists of the same type, so that patients are no longer strictly nested within therapists, creating a 'multiple-membership' relationship between patients and therapists. This paper considers methods of analysis and sample size estimation for trials with multiple-membership clustering effects. It is motivated by a trial of a psychotherapy for the treatment of adolescent depression with cognitive behavioural therapy. We tested methods and issues in a Monte Carlo simulation study, simulating trials with multiple membership. Results demonstrate satisfactory performance in terms of convergence and give estimates of the intra-cluster correlation coefficient and empirical test size similar to a simple hierarchical design. We derive formulae for sample size and power for multiple-membership trial designs. We then compare estimates of power from this formula with empirical power derived from the simulation study. Finally, we show that we can easily extend formulae for sample size and power to allow consideration of power and sample size for certain types of more complex interventions. These include situations where therapists of different types deliver separate components of the intervention, creating a cross-classified relationship, or where several therapists deliver a group-administered treatment, creating further levels. Copyright © 2012 John Wiley & Sons, Ltd.

  5. Knowledge-based approach to multiple-transaction processing and distributed data-base design

    SciTech Connect

    Park, J.T.

    1987-01-01

    The collective processing of multiple transactions in a data-base system has recently received renewed attention due to its capability of improving the overall performance of a data-base system and its applicability to the design of knowledge-based expert systems and extensible data-base systems. This dissertation consists of two parts. The first part presents a new knowledge-based approach to the problems of processing multiple concurrent queries and distributing replicated data objects for further improvement of the overall system performance. The second part deals with distributed database design, i.e., designing horizontal fragments using a semantic knowledge, and allocating data in a distributed environment. The semantic knowledge on data such as functional dependencies and semantic-data-integrity constraints are newly exploited for the identification of subset relationships between intermediate results of query executions involving joins, such that the (intermediate) results of queries can be utilized for the efficient processing of other queries. The expertise on the collective processing of multiple transactions is embodied into the rules of a rule-based expert system, MTP (Multiple Transaction Processor). In the second part, MTP is applied for the determination of horizontal fragments exploiting the semantic knowledge. Heuristics for allocating data in local area networks are developed.

  6. Multiplicity

    DTIC Science & Technology

    1991-04-01

    practice as a "[descent] into that inner circle of the Inferno where the damned endlessly degate multiplicity for sentencing." United States v. Barnard...select the charges to be brought in a particular case"). 19 Brown v. Ohio, 432 U.S. 161, 165 (1977). 20 Whalen v. United States, 445 U.S. at 689. 21...parte Lange, 8-5 U.S. (19 Wall.) 163 (1874). Cf. Brown v. Ohio, 432 U.S. at 165 ("once the legislature has acted courts may not impose more than one

  7. Concentration gradient limiter designs for incident plane waves and multiple chromophores

    NASA Astrophysics Data System (ADS)

    McLean, Daniel G.

    1998-10-01

    A design method for reverse saturable absorbing (RSA) dye concentration gradient limiters, termed here the Absorption Diffraction Balance (ADB) design method, is used to produce designs for multiple chromophores and is extended to allow incident plane waves. The ADB design method is reviewed for Gaussian beams applied to a constant fluence design and a linear fluence design. These two designs are combined to allow different dyes to be used in different portions of the limiter. It is found that this hybrid design significantly enhances performance under some circumstances. It is also shown to reduce the probability of dye photodegradation. The ADB design method is extended to allow for incident plane waves or a top-hat beam profile. The field at the geometric shadow edge, expressed in terms of Lommel functions, is shown to closely match the Gaussian field when the incident irradiance, power, and second moments are the same. Since the irradiance distribution is not monotonically increasing in the focal region, the required concentration distribution has regions of negative concentration, i.e. gain regions. These designs are useful for initiating numerical nonlinear beam propagation studies.

  8. Modified Esthetic Splint Design for Management of Multiple Traumatic Injuries in Children: A Case Report

    PubMed Central

    Garla, Bharath Kumar; Deshmukh, Seema; Murthy, Prashanth Sadashiva; Satish, G

    2015-01-01

    Traumatic injuries to the dento-alveolar structures are emergencies that compromise the quality of life of the patients. In addition to symptomatic management, definitive functional restoration and suitable rehabilitation becomes a major treatment objective in such cases. The dynamics of the traumatic forces may cause multiple injuries of different grades to the oral and para-oral structures, which makes comprehensive management a greater challenge to the dentist. The present case report elaborates a modified esthetic splint designed to treat multiple dental injuries in children, which can promote healing, restore optimal functionality along with esthetic rehabilitation to psychologically benefit the child during the time of recovery. PMID:26435631

  9. Digital Dashboard Design Using Multiple Data Streams for Disease Surveillance With Influenza Surveillance as an Example

    PubMed Central

    Cheng, Calvin KY; Ip, Dennis KM; Cowling, Benjamin J; Ho, Lai Ming; Leung, Gabriel M

    2011-01-01

    Background Great strides have been made exploring and exploiting new and different sources of disease surveillance data and developing robust statistical methods for analyzing the collected data. However, there has been less research in the area of dissemination. Proper dissemination of surveillance data can facilitate the end user's taking of appropriate actions, thus maximizing the utility of effort taken from upstream of the surveillance-to-action loop. Objective The aims of the study were to develop a generic framework for a digital dashboard incorporating features of efficient dashboard design and to demonstrate this framework by specific application to influenza surveillance in Hong Kong. Methods Based on the merits of the national websites and principles of efficient dashboard design, we designed an automated influenza surveillance digital dashboard as a demonstration of efficient dissemination of surveillance data. We developed the system to synthesize and display multiple sources of influenza surveillance data streams in the dashboard. Different algorithms can be implemented in the dashboard for incorporating all surveillance data streams to describe the overall influenza activity. Results We designed and implemented an influenza surveillance dashboard that utilized self-explanatory figures to display multiple surveillance data streams in panels. Indicators for individual data streams as well as for overall influenza activity were summarized in the main page, which can be read at a glance. Data retrieval function was also incorporated to allow data sharing in standard format. Conclusions The influenza surveillance dashboard serves as a template to illustrate the efficient synthesization and dissemination of multiple-source surveillance data, which may also be applied to other diseases. Surveillance data from multiple sources can be disseminated efficiently using a dashboard design that facilitates the translation of surveillance information to public

  10. Design and implementation of GRID-based PACS in a hospital with multiple imaging departments

    NASA Astrophysics Data System (ADS)

    Yang, Yuanyuan; Jin, Jin; Sun, Jianyong; Zhang, Jianguo

    2008-03-01

    Usually, there were multiple clinical departments providing imaging-enabled healthcare services in enterprise healthcare environment, such as radiology, oncology, pathology, and cardiology, the picture archiving and communication system (PACS) is now required to support not only radiology-based image display, workflow and data flow management, but also to have more specific expertise imaging processing and management tools for other departments providing imaging-guided diagnosis and therapy, and there were urgent demand to integrate the multiple PACSs together to provide patient-oriented imaging services for enterprise collaborative healthcare. In this paper, we give the design method and implementation strategy of developing grid-based PACS (Grid-PACS) for a hospital with multiple imaging departments or centers. The Grid-PACS functions as a middleware between the traditional PACS archiving servers and workstations or image viewing clients and provide DICOM image communication and WADO services to the end users. The images can be stored in distributed multiple archiving servers, but can be managed with central mode. The grid-based PACS has auto image backup and disaster recovery services and can provide best image retrieval path to the image requesters based on the optimal algorithms. The designed grid-based PACS has been implemented in Shanghai Huadong Hospital and been running for two years smoothly.

  11. Nanohole Arrays of Mixed Designs and Microwriting for Simultaneous and Multiple Protein Binding Studies

    PubMed Central

    Ji, Jin; Yang, Jiun-Chan; Larson, Dale N.

    2009-01-01

    We demonstrate using nanohole arrays of mixed designs and a microwriting process based on dip-pen nanolithography to monitor multiple, different protein binding events simultaneously in real time based on the intensity of Extraordinary Optical Transmission of nanohole arrays. The microwriting process and small footprint of the individual nanohole arrays enabled us to observe different binding events located only 16μm apart, achieving high spatial resolution. We also present a novel concept that incorporates nanohole arrays of different designs to improve confidence and accuracy of binding studies. For proof of concept, two types of nanohole arrays, designed to exhibit opposite responses to protein bindings, were fabricated on one transducer. Initial studies indicate that the mixed designs could help to screen out artifacts such as protein intrinsic signals, providing improved accuracy of binding interpretation. PMID:19297143

  12. Development of a turbomachinery design optimization procedure using a multiple-parameter nonlinear perturbation method

    NASA Technical Reports Server (NTRS)

    Stahara, S. S.

    1984-01-01

    An investigation was carried out to complete the preliminary development of a combined perturbation/optimization procedure and associated computational code for designing optimized blade-to-blade profiles of turbomachinery blades. The overall purpose of the procedures developed is to provide demonstration of a rapid nonlinear perturbation method for minimizing the computational requirements associated with parametric design studies of turbomachinery flows. The method combines the multiple parameter nonlinear perturbation method, successfully developed in previous phases of this study, with the NASA TSONIC blade-to-blade turbomachinery flow solver, and the COPES-CONMIN optimization procedure into a user's code for designing optimized blade-to-blade surface profiles of turbomachinery blades. Results of several design applications and a documented version of the code together with a user's manual are provided.

  13. A small n sequential multiple assignment randomized trial design for use in rare disease research.

    PubMed

    Tamura, Roy N; Krischer, Jeffrey P; Pagnoux, Christian; Micheletti, Robert; Grayson, Peter C; Chen, Yeh-Fong; Merkel, Peter A

    2016-01-01

    Clinical trials in rare diseases are difficult to conduct due to the limited number of patients available with each disorder. We developed a Phase 2 trial which is a small n sequential multiple assignment randomized trial (snSMART) design to test several treatments for a rare disease for which no standard therapy exists. This paper illustrates the design, sample size estimation and operating characteristics of an snSMART. We investigate the performance of a class of weighted Z statistics via computer simulations. We demonstrate the increase in power over traditional single stage designs, and indicate how the power changes as a function of the weight given to each stage. The snSMART design is promising in a rare disease setting where several alternative treatments are under consideration and small sample sizes are necessary. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Self-similar flow channel designs for parallel multiscale transport of multiple fluid species

    NASA Astrophysics Data System (ADS)

    Lee, Kenneth; Savas, Omer

    2011-11-01

    The need for multiscale fluid transport arises in a number of engineering applications involving fluid delivery or collection over a range of different lengthscales. A ``tree-shaped'' system of flow channels has been an efficient transport solution commonly practiced by biomimetics. There has been much work in optimizing these dendritic flow systems, primarily for cooling applications. However, most designs can be costly to manufacture and limited in scalability. Moreover, most systems are restricted to the transport of a single fluid species. This work explores the feasibility of self-similar flow channel designs to provide parallel multiscale transport of multiple fluid species. The self-similar characteristic of these designs simplifies manufacturing and allows for flexible scalability. Prototypes for the parallel transport of one and two independent fluid species are supported with analytical theory and experimental work. Designs for three and four species are presented as well. Supported by Joint Center for Artificial Photosynthesis (JCAP)

  15. Design of e-Science platform for biomedical imaging research cross multiple academic institutions and hospitals

    NASA Astrophysics Data System (ADS)

    Zhang, Jianguo; Zhang, Kai; Yang, Yuanyuan; Ling, Tonghui; Wang, Tusheng; Wang, Mingqing; Hu, Haibo; Xu, Xuemin

    2012-02-01

    More and more image informatics researchers and engineers are considering to re-construct imaging and informatics infrastructure or to build new framework to enable multiple disciplines of medical researchers, clinical physicians and biomedical engineers working together in a secured, efficient, and transparent cooperative environment. In this presentation, we show an outline and our preliminary design work of building an e-Science platform for biomedical imaging and informatics research and application in Shanghai. We will present our consideration and strategy on designing this platform, and preliminary results. We also will discuss some challenges and solutions in building this platform.

  16. Statistical Power of Randomization Tests Used with Multiple-Baseline Designs.

    ERIC Educational Resources Information Center

    Ferron, John; Sentovich, Chris

    2002-01-01

    Estimated statistical power for three randomization tests used with multiple-baseline designs using Monte Carlo methods. For an effect size of 0.5, none of the tests provided an adequate level of power, and for an effect size of 1.0, power was adequate for the Koehler-Levin test and the Marascuilo-Busk test only when the series length was long and…

  17. Statistical Power of Randomization Tests Used with Multiple-Baseline Designs.

    ERIC Educational Resources Information Center

    Ferron, John; Sentovich, Chris

    2002-01-01

    Estimated statistical power for three randomization tests used with multiple-baseline designs using Monte Carlo methods. For an effect size of 0.5, none of the tests provided an adequate level of power, and for an effect size of 1.0, power was adequate for the Koehler-Levin test and the Marascuilo-Busk test only when the series length was long and…

  18. Automatic differentiation for design sensitivity analysis of structural systems using multiple processors

    NASA Technical Reports Server (NTRS)

    Nguyen, Duc T.; Storaasli, Olaf O.; Qin, Jiangning; Qamar, Ramzi

    1994-01-01

    An automatic differentiation tool (ADIFOR) is incorporated into a finite element based structural analysis program for shape and non-shape design sensitivity analysis of structural systems. The entire analysis and sensitivity procedures are parallelized and vectorized for high performance computation. Small scale examples to verify the accuracy of the proposed program and a medium scale example to demonstrate the parallel vector performance on multiple CRAY C90 processors are included.

  19. New opioid designed multiple ligand from Dmt-Tic and morphinan pharmacophores.

    PubMed

    Neumeyer, John L; Peng, Xuemei; Knapp, Brian I; Bidlack, Jean M; Lazarus, Lawrence H; Salvadori, Severo; Trapella, Claudio; Balboni, Gianfranco

    2006-09-07

    Here, we report the synthesis of a designed multi-pharmacophore ligand derived from the linkage of a delta selective peptide antagonist (Dmt-Tic) and a mu/kappa morphinan agonist butorphan (MCL 101) through a two methylene spacer. The new compound MCL 450 maintains the same characteristics as those the two reference compounds. MCL 450 represents a useful starting point for the synthesis of other multiple opioid ligands endowed with analgesic properties with low tolerance and dependence.

  20. Design of a Multiple-Input SC DC-DC Converter Realizing Long Battery Runtime

    NASA Astrophysics Data System (ADS)

    Eguchi, Kei; Pongswatd, Sawai; Julsereewong, Amphawan; Tirasesth, Kitti; Sasaki, Hirofumi; Inoue, Takahiro

    A multiple-input switched-capacitor DC-DC converter which can realize long battery runtime is proposed in this letter. Unlike conventional converters for a back-lighting application, the proposed converter drives some LEDs by converting energy from solar cells. Furthermore, the proposed converter can charge a lithium battery when an output load is light. The validity of circuit design is confirmed by theoretical analyses, simulations, and experiments.

  1. Design of the cooling systems for the multiplicity and vertex detector

    SciTech Connect

    Bernardin, J.D.; Cunningham, R.

    1997-11-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is being constructed to investigate a phase of matter termed the quark-gluon plasma. The plasma will be produced through the collision of two heavy ions. The multiplicity and vertex detector (MVD) located in the center of PHENIX will characterize the events, determine the collision point, and act as a central trigger. This report presents the final mechanical designs of the cooling systems for the Multiplicity and Vertex Detector (MVD). In particular, the design procedure and layouts are discussed for two different air cooling systems for the multichip modules and MVD enclosure, and a liquid cooling system for the low dropout voltage regulators. First of all, experimental prototype cooling system test results used to drive the final mechanical designs are summarized and discussed. Next, the cooling system requirements and design calculation for the various subsystem components are presented along with detailed lists of supply vendors, components, and costs. Finally, safety measures incorporated in the final mechanical design and operation procedures for each of the subsystems are detailed.

  2. Design of multiple sequence alignment algorithms on parallel, distributed memory supercomputers.

    PubMed

    Church, Philip C; Goscinski, Andrzej; Holt, Kathryn; Inouye, Michael; Ghoting, Amol; Makarychev, Konstantin; Reumann, Matthias

    2011-01-01

    The challenge of comparing two or more genomes that have undergone recombination and substantial amounts of segmental loss and gain has recently been addressed for small numbers of genomes. However, datasets of hundreds of genomes are now common and their sizes will only increase in the future. Multiple sequence alignment of hundreds of genomes remains an intractable problem due to quadratic increases in compute time and memory footprint. To date, most alignment algorithms are designed for commodity clusters without parallelism. Hence, we propose the design of a multiple sequence alignment algorithm on massively parallel, distributed memory supercomputers to enable research into comparative genomics on large data sets. Following the methodology of the sequential progressiveMauve algorithm, we design data structures including sequences and sorted k-mer lists on the IBM Blue Gene/P supercomputer (BG/P). Preliminary results show that we can reduce the memory footprint so that we can potentially align over 250 bacterial genomes on a single BG/P compute node. We verify our results on a dataset of E.coli, Shigella and S.pneumoniae genomes. Our implementation returns results matching those of the original algorithm but in 1/2 the time and with 1/4 the memory footprint for scaffold building. In this study, we have laid the basis for multiple sequence alignment of large-scale datasets on a massively parallel, distributed memory supercomputer, thus enabling comparison of hundreds instead of a few genome sequences within reasonable time.

  3. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Guidelines on the design of a multiple-dose in... Guidelines on the design of a multiple-dose in vivo bioavailability study. (a) Basic principles. (1) In... therapeutic moiety in the body. (2) The test product and the reference material should be administered to...

  4. A standardized mean difference effect size for multiple baseline designs across individuals.

    PubMed

    Hedges, Larry V; Pustejovsky, James E; Shadish, William R

    2013-12-01

    Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and medicine. Emerging standards for single-case designs have focused attention on methods for summarizing and meta-analyzing findings and on the need for effect sizes indices that are comparable to those used in between-subjects designs. In the previous work, we discussed how to define and estimate an effect size that is directly comparable to the standardized mean difference often used in between-subjects research based on the data from a particular type of single-case design, the treatment reversal or (AB)(k) design. This paper extends the effect size measure to another type of single-case study, the multiple baseline design. We propose estimation methods for the effect size and its variance, study the estimators using simulation, and demonstrate the approach in two applications. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Error-resilient low-delay H.264/802.11 transmission via cross-layer coding with feedback channel

    NASA Astrophysics Data System (ADS)

    Chiew, Tuan-Kiang; Hill, Paul; Ferre, Pierre; Agrafiotis, Dimitris; Chung-How, James T. H.; Nix, Andy; Bull, David R.

    2005-07-01

    We propose a method of providing error resilient H.264 video over 802.11 wireless channels by using a feedback mechanism which does not incur an additional delay typically found in ARQ-type feedback. Our system uses the TCP/IP and UDP/IP protocols, located between the medium access control (MAC) layer of 802.11, and the H.264 video application layer. The UDP protocol is used to transfer time sensitive video data without delay; however, packet losses introduce excessive artifacts which propagate to subsequent frames. Error resilience is achieved by a feedback mechanism-the decoder conveys the packet-loss information as small TCP packets to the video source as negative acknowledgements. By using multiple reference frames, slice-based coding and timely intra-refresh, the encoder makes use of this feedback information to perform subsequent temporal prediction without propagating the error to future frames. We take static measurements of the actual channel and use the packet loss and delay patterns to test our algorithms. Simulations show an improvement of 0.5~5 dB in PSNR over plain UDP-based video transmission. Our method improves the overall quality of service of interactive video transmission over wireless LAN; it can be used as a model for future media-aware wireless network protocol designs.

  6. NCCN Work Group Report: Designing Clinical Trials in the Era of Multiple Biomarkers and Targeted Therapies

    PubMed Central

    Venook, Alan P.; Arcila, Maria E.; Benson, Al B.; Berry, Donald A.; Camidge, David Ross; Carlson, Robert W.; Choueiri, Toni K.; Guild, Valerie; Kalemkerian, Gregory P.; Kurzrock, Razelle; Lovly, Christine M.; McKee, Amy E.; Morgan, Robert J.; Olszanski, Anthony J.; Redman, Mary W.; Stearns, Vered; McClure, Joan; Birkeland, Marian L.

    2016-01-01

    Defining treatment susceptible or resistant populations of cancer patients through the use of genetically defined biomarkers has revolutionized cancer care in recent years for some disease/patient groups. Research continues to show that histologically defined diseases are diverse in their expression of unique mutations or other genetic alterations, however, which presents both opportunities for the development of personalized cancer treatments, but increased difficulty in testing these therapies because potential patient populations are divided into ever-smaller numbers. To address some of the growing challenges in biomarker development and clinical trial design, NCCN assembled a group of experts across specialties and solid tumor disease types to begin to define the problems and to consider alternate ways of designing clinical trials in the era of multiple biomarkers and targeted therapies. Results from that discussion are presented, focusing on issues of clinical trial design from the perspective of statisticians, clinical researchers, regulators, pathologists and information developers. PMID:25361808

  7. Design and optimization of an RF energy harvesting system from multiple sources

    NASA Astrophysics Data System (ADS)

    Ali, Mai; Albasha, Lutfi; Qaddoumi, Nasser

    2013-05-01

    This paper presents the design and optimization of an RF energy harvesting system from multiple sources. The RF power is harvested from four frequency bands representing five wireless systems, namely GSM, UMTS, DTV, Wi-Fi, and road tolling system. A Schottky diode model was developed based on which an RF-DC rectifier joined with a voltage multiplier circuits were designed. The simulation results of the complete RF harvesting system showed superior performance to similar state of the art systems. To further optimize the design, and to eliminate use of a non-standard CMOS process associated with Schottky diodes, the Schottky diode based rectifier was replaced by diode connected transistor configuration based on self-threshold cancellation (SVC) technique.

  8. Designed multiple ligands: an emerging anti-HIV drug discovery paradigm.

    PubMed

    Zhan, Peng; Liu, Xinyong

    2009-01-01

    Currently, the effect of AIDS single-target chemotherapy is severely compromised by the quick emergence of resistant HIV strains. Highly active antiretroviral therapy (HAART) combines HIV reverse transcriptase inhibitors with protease inhibitors or integrase inhibitors, and successfully suppresses HIV viral load to an undetectable level, dramatically improving the life quality of AIDS patients. However, the benefits of this approach are often compromised by poor patient compliance. Recently, there has been a move toward multicomponent drugs whereby two or more agents are coformulated in a single tablet to make dosing regimes simpler and thereby to improve patient compliance, but there are significant risks involved in the development of multicomponent drugs. Designed multiple ligands (DMLs) therapy as an emerging anti-HIV drug discovery paradigm, using a single entity to inhibit multitargets could yield improved patient compliance, thus reducing the likelihood of drug resistance. The exploration of such multifunctional ligands has proven valuable for anti-HIV leads discovery. However, presently many multifunctional scaffolds were first discovered by serendipity or screening; rational design by combining existing monofunctional scaffolds remains an enormous challenge. A key issue in the design of multiple ligands is attaining a balanced activity at each target of interest while simultaneously achieving a wider selectivity and a suitable pharmacokinetic profile. This review of literature examples introduce numerous attractive lead compounds, capable of interfering with different stages of HIV infection and AIDS pathogenesis, which reveals trends and insights that might provide valuable clues for novel anti-HIV drug design and help medicinal chemists discover the next generation of multiple ligands.

  9. Innovative tools for quality assessment: integrated quality criteria for review of multiple study designs (ICROMS).

    PubMed

    Zingg, W; Castro-Sanchez, E; Secci, F V; Edwards, R; Drumright, L N; Sevdalis, N; Holmes, A H

    2016-04-01

    With the aim to facilitate a more comprehensive review process in public health including patient safety, we established a tool that we have termed ICROMS (Integrated quality Criteria for the Review Of Multiple Study designs), which unifies, integrates and refines current quality criteria for a large range of study designs including qualitative research. Review, pilot testing and expert consensus. The tool is the result of an iterative four phase process over two years: 1) gathering of established criteria for assessing controlled, non-controlled and qualitative study designs; 2) pilot testing of a first version in two systematic reviews on behavioural change in infection prevention and control and in antibiotic prescribing; 3) further refinement and adding of additional study designs in the context of the European Centre for Disease Prevention and Control funded project 'Systematic review and evidence-based guidance on organisation of hospital infection control programmes' (SIGHT); 4) scrutiny by the pan-European expert panel of the SIGHT project, which had the objective of ensuring robustness of the systematic review. ICROMS includes established quality criteria for randomised studies, controlled before-and-after studies and interrupted time series, and incorporates criteria for non-controlled before-and-after studies, cohort studies and qualitative studies. The tool consists of two parts: 1) a list of quality criteria specific for each study design, as well as criteria applicable across all study designs by using a scoring system; 2) a 'decision matrix', which specifies the robustness of the study by identifying minimum requirements according to the study type and the relevance of the study to the review question. The decision matrix directly determines inclusion or exclusion of a study in the review. ICROMS was applied to a series of systematic reviews to test its feasibility and usefulness in the appraisal of multiple study designs. The tool was applicable

  10. Emotive imagery and children's night-time fears: a multiple baseline design evaluation.

    PubMed

    King, N; Cranstoun, F; Josephs, A

    1989-06-01

    Emotive imagery is a variant of systematic desensitization that has been used in the treatment of children's excessive fears. The purpose of this study was to evaluate the efficacy of emotive imagery as a fear reduction procedure using a multiple baseline design across subjects. Three children (6, 8 and 11 years old) with night-time fears participated in the study. The children showed marked behavioral improvements on a test for darkness toleration that was administered on alternate days in their homes. However, they reported experiencing very little fear in these tests. Over the intervention period fewer night-time behavioral disturbances were observed for two subjects. Parents expressed some concern about the darkness test but were satisfied with emotive imagery as a fear reduction procedure. As children's phobias are characterized by multiple processes, we recommend a combination of treatment procedures in clinical practice.

  11. Proposed variations of the stepped-wedge design can be used to accommodate multiple interventions.

    PubMed

    Lyons, Vivian H; Li, Lingyu; Hughes, James P; Rowhani-Rahbar, Ali

    2017-06-01

    Stepped-wedge design (SWD) cluster-randomized trials have traditionally been used for evaluating a single intervention. We aimed to explore design variants suitable for evaluating multiple interventions in an SWD trial. We identified four specific variants of the traditional SWD that would allow two interventions to be conducted within a single cluster-randomized trial: concurrent, replacement, supplementation, and factorial SWDs. These variants were chosen to flexibly accommodate study characteristics that limit a one-size-fits-all approach for multiple interventions. In the concurrent SWD, each cluster receives only one intervention, unlike the other variants. The replacement SWD supports two interventions that will not or cannot be used at the same time. The supplementation SWD is appropriate when the second intervention requires the presence of the first intervention, and the factorial SWD supports the evaluation of intervention interactions. The precision for estimating intervention effects varies across the four variants. Selection of the appropriate design variant should be driven by the research question while considering the trade-off between the number of steps, number of clusters, restrictions for concurrent implementation of the interventions, lingering effects of each intervention, and precision of the intervention effect estimates. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Learning and cognitive fatigue trajectories in multiple sclerosis defined using a burst measurement design.

    PubMed

    Holtzer, Roee; Foley, Frederick; D'Orio, Vanessa; Spat, Jessica; Shuman, Melissa; Wang, Cuiling

    2013-10-01

    Compromised learning and cognitive fatigue are critical clinical features in multiple sclerosis. This study was designed to determine the effect of repeated exposures within and across study visits on performance measures of learning and cognitive fatigue in relapsing-remitting multiple sclerosis (RRMS). Thirty patients with RRMS and 30 controls were recruited. Using a burst measurement design (i.e. repeated assessments within and across study visits) the oral version of the Symbol Digit Modalities Test (SDMT) was administered three times during the baseline and two consecutive monthly follow-up visits for a total of nine test administrations. Learning was assessed within and across study visits whereas cognitive fatigue was assessed during the course of each test administration that was divided into three 30-second intervals. Linear mixed-effect models revealed compromised learning within (95% CI: 2.6355 to 3.9867) and across (95% CI: 1.3250 to 3.1861) visits and worse cognitive fatigue (95% CI: -2.1761 to -0.1720) in patients with RRMS compared with controls. Among patients with RRMS, worse self-rated cognitive dysfunction predicted poor learning within (95% CI: -0.1112 to -0.0020) and across (95% CI: -0.0724 to -0.0106) visits. Burst design is optimal to study learning and cognitive fatigue. This methodology, using the SDMT or other time-efficient tests as outcome measures, can be successfully implemented in longitudinal studies and clinical trials.

  13. A water quality monitoring network design using fuzzy theory and multiple criteria analysis.

    PubMed

    Chang, Chia-Ling; Lin, You-Tze

    2014-10-01

    A proper water quality monitoring design is required in a watershed, particularly in a water resource protected area. As numerous factors can influence the water quality monitoring design, this study applies multiple criteria analysis to evaluate the suitability of the water quality monitoring design in the Taipei Water Resource Domain (TWRD) in northern Taiwan. Seven criteria, which comprise percentage of farmland area, percentage of built-up area, amount of non-point source pollution, green cover ratio, landslide area ratio, ratio of over-utilization on hillsides, and density of water quality monitoring stations, are selected in the multiple criteria analysis. The criteria are normalized and weighted. The weighted method is applied to score the subbasins. The density of water quality stations needs to be increased in priority in the subbasins with a higher score. The fuzzy theory is utilized to prioritize the need for a higher density of water quality monitoring stations. The results show that the need for more water quality stations in subbasin 2 in the Bei-Shih Creek Basin is much higher than those in the other subbasins. Furthermore, the existing water quality station in subbasin 2 requires maintenance. It is recommended that new water quality stations be built in subbasin 2.

  14. Multiple harmonic frequencies resonant cavity design and half-scale prototype measurements for a fast kicker

    NASA Astrophysics Data System (ADS)

    Huang, Yulu; Wang, Haipeng; Rimmer, Robert A.; Wang, Shaoheng; Guo, Jiquan

    2016-12-01

    Quarter wavelength resonator (QWR) based deflecting cavities with the capability of supporting multiple odd-harmonic modes have been developed for an ultrafast periodic kicker system in the proposed Jefferson Lab Electron Ion Collider (JLEIC, formerly MEIC). Previous work on the kicking pulse synthesis and the transverse beam dynamics tracking simulations show that a flat-top kicking pulse can be generated with minimal emittance growth during injection and circulation of the cooling electron bunches. This flat-top kicking pulse can be obtained when a DC component and 10 harmonic modes with appropriate amplitude and phase are combined together. To support 10 such harmonic modes, four QWR cavities are used with 5, 3, 1, and 1 modes, respectively. In the multiple-mode cavities, several slightly tapered segments of the inner conductor are introduced to tune the higher order deflecting modes to be harmonic, and stub tuners are used to fine tune each frequency to compensate for potential errors. In this paper, we summarize the electromagnetic design of the five-mode cavity, including the geometry optimization to get high transverse shunt impedance, the frequency tuning and sensitivity analysis, and the single loop coupler design for coupling to all of the harmonic modes. In particular we report on the design and fabrication of a half-scale copper prototype of this proof-of-principle five-odd-mode cavity, as well as the rf bench measurements. Finally, we demonstrate mode superposition in this cavity experimentally, which illustrates the kicking pulse generation concept.

  15. Effective design of multiple hollow cathode electrode to enhance the density of rf capacitively coupled plasma

    SciTech Connect

    Lee, H. S.; Lee, Y. S.; Seo, S. H.; Chang, H. Y.

    2010-08-23

    Multiple-hole electrode rf capacitively coupled plasma is experimentally studied to determine the optimum condition for high-density plasma discharge. The plasma density was measured at various pressures, hole diameters, rf currents, and gas species conditions. The bulk plasma intrusion in the hole and the ionization avalanche in the sheath region facilitated high-density plasma generation when the diameter of the hole is slightly wider than triple the sheath length. The analytic design of the efficient multihole electrode for high-density rf capacitively coupled plasma discharge will be discussed.

  16. Application of multiple criteria decision methods in space exploration initiative design and planning

    NASA Technical Reports Server (NTRS)

    Masud, Abu S. M.

    1991-01-01

    Fellowship activities were directed towards the identification of opportunities for application of the Multiple Criteria Decision Making (MCDM) techniques in the Space Exploration Initiative (SEI) domain. I identified several application possibilities and proposed demonstration application in these three areas: evaluation and ranking of SEI architectures, space mission planning and selection, and space system design. Here, only the first problem is discussed. The most meaningful result of the analysis is the wide separation between the two top ranked architectures, indicating a significant preference difference between them. It must also be noted that the final ranking reflects, to some extent, the biases of the evaluators and their understanding of the architecture.

  17. Design and performance evaluation of a wideband FM spread-spectrum multiple-access system

    NASA Technical Reports Server (NTRS)

    Wachsman, R. H.; Ghais, A. F.

    1971-01-01

    The system described performs the tracking and communications functions of a tracking and data relay satellite system (TDRS). The spread-spectrum signal format is achieved through wide deviation FM by a sinusoidal subcarrier unique to each multiple-access user. A compound phase-locked loop tracks carrier and subcarrier and demodulates data and ranging signals. Design parameters of user and ground terminals for TDRS are given. Acquisition procedures are described. Performance analyses are presented including the effects of noise, RFI, multipath and other users.

  18. Effective design of multiple hollow cathode electrode to enhance the density of rf capacitively coupled plasma

    NASA Astrophysics Data System (ADS)

    Lee, H. S.; Lee, Y. S.; Seo, S. H.; Chang, H. Y.

    2010-08-01

    Multiple-hole electrode rf capacitively coupled plasma is experimentally studied to determine the optimum condition for high-density plasma discharge. The plasma density was measured at various pressures, hole diameters, rf currents, and gas species conditions. The bulk plasma intrusion in the hole and the ionization avalanche in the sheath region facilitated high-density plasma generation when the diameter of the hole is slightly wider than triple the sheath length. The analytic design of the efficient multihole electrode for high-density rf capacitively coupled plasma discharge will be discussed.

  19. Minimum weight design of rotorcraft blades with multiple frequency and stress constraints

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Aditi; Walsh, Joanne L.

    1988-01-01

    Minimum weight designs of helicopter rotor blades with constraints on multiple coupled flap-lag natural frequencies are studied. Constraints are imposed on the minimum value of the blade autorotational inertia to ensure sufficient rotary inertia to autorotate in case of engine failure and on stresses to guard against structural failure due to blade centrifugal forces. Design variables include blade taper ratio, dimensions of the box beam located inside the airfoil and magnitudes of nonstructural weights. The program CAMRAD is used for the blade modal analysis; the program CONMIN is used for the optimization. A linear approximation involving Taylor series expansion is used to reduce the analysis effort. The procedure contains a sensitivity analysis consisting of analytical derivatives for objective function and constraints on autorotational inertia and stresses. Central finite difference derivatives are used for frequency constraints. Optimal designs are obtained for both rectangular and tapered blades. Using this method, it is possible to design a rotor blade with reduced weight, when compared to a baseline blade, while satisfying all the imposed design requirements.

  20. Use of a randomized multiple baseline design: rationale and design of the spirited life holistic health intervention study.

    PubMed

    Proeschold-Bell, Rae Jean; Swift, Robin; Moore, H Edgar; Bennett, Gary; Li, Xiang-Fang; Blouin, Rachel; Williams, Virginia P; Williams, Redford B; Toole, David

    2013-07-01

    Clergy suffer from high rates of obesity, chronic disease, and depression, and simultaneously underestimate the toll these take on their daily functioning. Health interventions are needed for clergy and may be tailored to their occupational context and theological beliefs. Few studies have sought to improve clergy health. No prior studies have utilized a randomized design. Spirited Life is a randomized, multiple baseline study that offered enrollment to nearly all United Methodist Church clergy in North Carolina in fall 2010. A total of 1114 clergy (response rate = 64%) enrolled. Using a multiple baseline design, we randomized participants to three cohorts. Each cohort began the health intervention in one of three consecutive years. The third cohort served as a randomized waitlist control cohort, allowing comparisons between the first and third cohorts. The two-year Spirited Life intervention consists of: 1) a theological underpinning for health stewardship based on incarnation, grace, and response and delivered during workshops; 2) the stress management program Williams LifeSkills; 3) Naturally Slim, an online weight loss program; 4) phone contact with a Wellness Advocate; and 5) $500 small grants for health goals. Metabolic syndrome is the primary endpoint. Stress and depressive severity are secondary endpoints. We measured each construct before, twice during, and at the end of the two-year intervention. Study outcomes, to be published after follow-up data are gathered, will provide evidence of the effectiveness of the combined intervention components of Spirited Life. If successful, the intervention may be considered for use with other clergy and faith populations. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. An intelligent, knowledge-based multiple criteria decision making advisor for systems design

    NASA Astrophysics Data System (ADS)

    Li, Yongchang

    In systems engineering, design and operation of systems are two main problems which always attract researcher's attentions. The accomplishment of activities in these problems often requires proper decisions to be made so that the desired goal can be achieved, thus, decision making needs to be carefully fulfilled in the design and operation of systems. Design is a decision making process which permeates through out the design process, and is at the core of all design activities. In modern aircraft design, more and more attention is paid to the conceptual and preliminary design phases so as to increase the odds of choosing a design that will ultimately be successful at the completion of the design process, therefore, decisions made during these early design stages play a critical role in determining the success of a design. Since aerospace systems are complex systems with interacting disciplines and technologies, the Decision Makers (DMs) dealing with such design problems are involved in balancing the multiple, potentially conflicting attributes/criteria, transforming a large amount of customer supplied guidelines into a solidly defined set of requirement definitions. Thus, one could state with confidence that modern aerospace system design is a Multiple Criteria Decision Making (MCDM) process. A variety of existing decision making methods are available to deal with this type of decision problems. The selection of the most appropriate decision making method is of particular importance since inappropriate decision methods are likely causes of misleading engineering design decisions. With no sufficient knowledge about each of the methods, it is usually difficult for the DMs to find an appropriate analytical model capable of solving their problems. In addition, with the complexity of the decision problem and the demand for more capable methods increasing, new decision making methods are emerging with time. These various methods exacerbate the difficulty of the selection

  2. Multiple Regression Analysis Approach To The Automatic Design Of Adaptive Image Processing Systems

    NASA Astrophysics Data System (ADS)

    Otsu, N.

    1984-01-01

    Multiple regression analysis for modeling the correspondence between a set of input variates and an output variate or a set of variates seems to be one of the most promising and direct approaches to automatically designing adaptive (or learning) systems for image pro-cessing and computer vision. Some approaches are shown with experimental results, such as automatic design of adaptive filters for image enhancement and restoration by giving the input image and the desired out-put image as a pair. The advantage of such an approach is the capability to simulate in an automatic and gen-eral way the functional "black boxes" (solutions) which are imposed by real problems regard-less of their inner detail, while the usual approaches are based on the so-called trial and error methods where any method proposed is repeatedly tried and checked for its results.

  3. Cryogenic Propulsion Stage (CPS) Configuration in Support of NASA's Multiple Design Reference Missions (DRMs)

    NASA Technical Reports Server (NTRS)

    Hanna, Stephen G.; Jones, David L.; Creech, Stephen D.; Lawrence, Thomas D.

    2012-01-01

    In support of the National Aeronautics and Space Administration's (NASA) Human Exploration and Operations Mission Directorate (HEOMD), the Space Launch System (SLS) is being designed for safe, affordable, and sustainable human and scientific exploration missions beyond Earth's or-bit (BEO). The SLS Team is tasked with developing a system capable of safely and repeatedly lofting a new fleet of spaceflight vehicles beyond Earth orbit. The Cryogenic Propulsion Stage (CPS) is a key enabler for evolving the SLS capability for BEO missions. This paper reports on the methodology and initial recommendations relative to the CPS, giving a brief retrospective of early studies on this promising propulsion hardware. This paper provides an overview of the requirements development and CPS configuration in support of NASA's multiple Design Reference Missions (DRMs).

  4. A Bayesian design for phase II clinical trials with delayed responses based on multiple imputation

    PubMed Central

    Cai, Chunyan; Liu, Suyu; Yuan, Ying

    2015-01-01

    Interimmonitoring is routinely conducted in phase II clinical trials to terminate the trial early if the experimental treatment is futile. Interim monitoring requires that patients’ responses be ascertained shortly after the initiation of treatment so that the outcomes are known by the time the interim decision must be made. However, in some cases, response outcomes require a long time to be assessed, which causes difficulties for interim monitoring. To address this issue, we propose a Bayesian trial design to allow for continuously monitoring phase II clinical trials in the presence of delayed responses. We treat the delayed responses as missing data and handle them using a multiple imputation approach. Extensive simulations show that the proposed design yields desirable operating characteristics under various settings and dramatically reduces the trial duration. PMID:24817556

  5. Design of a dynamic model of genes with multiple autonomous regulatory modules by evolutionary computations

    PubMed Central

    Spirov, Alexander V.; Holloway, David M.

    2010-01-01

    A new approach to design a dynamic model of genes with multiple autonomous regulatory modules by evolutionary computations is proposed. The approach is based on Genetic Algorithms (GA), with new crossover operators especially designed for these purposes. The new operators use local homology between parental strings to preserve building blocks found by the algorithm. The approach exploits the subbasin-portal architecture of the fitness functions suitable for this kind of evolutionary modeling. This architecture is significant for Royal Road class fitness functions. Two real-life Systems Biology problems with such fitness functions are implemented here: evolution of the bacterial promoter rrnPl and of the enhancer of the Drosophila even-skipped gene. The effectiveness of the approach compared to standard GA is demonstrated on several benchmark and real-life tasks. PMID:20930945

  6. Design and operation of the multiple-pulse driver line on the OMEGA laser

    NASA Astrophysics Data System (ADS)

    Kosc, T. Z.; Kelly, J. H.; Hill, E. M.; Waxer, L. J.

    2016-05-01

    The multiple-pulse driver line (MPD) provides on-shot co-propagation of two separately generated pulse shapes in all 60 OMEGA beams at the Laboratory for Laser Energetics. Smoothing by spectral dispersion (SSD), which increases the laser bandwidth, can be applied to either one of the two pulse shapes, thereby enabling dynamic bandwidth reduction. The design of the MPD required careful consideration of beam combination as well as the minimum pulse separation for two pulses generated by two separate seed sources. A new combined-pulse-shape diagnostic needed to be designed and installed after the last SSD grating. The capability of MPD to reduce dynamic bandwidth has been used on a series of campaigns on OMEGA and the performance data are presented.

  7. Novel anti-HIV peptides containing multiple copies of artificially designed heptad repeat motifs

    SciTech Connect

    Shi Weiguo; Qi Zhi; Pan Chungen; Xue Na; Debnath, Asim K.; Qie Jiankun; Jiang Shibo Liu Keliang

    2008-10-03

    The peptidic anti-HIV drug T20 (Fuzeon) and its analog C34 share a common heptad repeat (HR) sequence, but they have different functional domains, i.e., pocket- and lipid-binding domains (PBD and LBD, respectively). We hypothesize that novel anti-HIV peptides may be designed by using artificial sequences containing multiple copies of HR motifs plus zero, one or two functional domains. Surprisingly, we found that the peptides containing only the non-natural HR sequences could significantly inhibit HIV-1 infection, while addition of PBD and/or LBD to the peptides resulted in significant improvement of anti-HIV-1 activity. These results suggest that these artificial HR sequences, which may serve as structural domains, could be used as templates for the design of novel antiviral peptides against HIV and other viruses with class I fusion proteins.

  8. Regulatory perspectives on multiplicity in adaptive design clinical trials throughout a drug development program.

    PubMed

    Wang, Sue-Jane; Hung, H M James; O'Neill, Robert

    2011-07-01

    A clinical research program for drug development often consists of a sequence of clinical trials that may begin with uncontrolled and nonrandomized trials, followed by randomized trials or randomized controlled trials. Adaptive designs are not infrequently proposed for use. In the regulatory setting, the success of a drug development program can be defined to be that the experimental treatment at a specific dose level including regimen and frequency is approved based on replicated evidence from at least two confirmatory trials. In the early stage of clinical research, multiplicity issues are very broad. What is the maximum tolerable dose in an adaptive dose escalation trial? What should the dose range be to consider in an adaptive dose-ranging trial? What is the minimum effective dose in an adaptive dose-response study given the tolerability and the toxicity observable in short term or premarketing trials? Is establishing the dose-response relationship important or the ability to select a superior treatment with high probability more important? In the later stage of clinical research, multiplicity problems can be formulated with better focus, depending on whether the study is for exploration to estimate or select design elements or for labeling consideration. What is the study objective for an early-phase versus a later phase adaptive clinical trial? How many doses are to be studied in the early exploratory adaptive trial versus in the confirmatory adaptive trial? Is the intended patient population well defined or is the applicable patient population yet to be adaptively selected in the trial due to the potential patient and/or disease heterogeneity? Is the primary efficacy endpoint well defined or still under discussion providing room for adaptation? What are the potential treatment indications that may adaptively lead to an intended-to-treat patient population and the primary efficacy endpoint? In this work we stipulate the multiplicity issues with adaptive

  9. SMET: systematic multiple enzyme targeting - a method to rationally design optimal strains for target chemical overproduction.

    PubMed

    Flowers, David; Thompson, R Adam; Birdwell, Douglas; Wang, Tsewei; Trinh, Cong T

    2013-05-01

    Identifying multiple enzyme targets for metabolic engineering is very critical for redirecting cellular metabolism to achieve desirable phenotypes, e.g., overproduction of a target chemical. The challenge is to determine which enzymes and how much of these enzymes should be manipulated by adding, deleting, under-, and/or over-expressing associated genes. In this study, we report the development of a systematic multiple enzyme targeting method (SMET), to rationally design optimal strains for target chemical overproduction. The SMET method combines both elementary mode analysis and ensemble metabolic modeling to derive SMET metrics including l-values and c-values that can identify rate-limiting reaction steps and suggest which enzymes and how much of these enzymes to manipulate to enhance product yields, titers, and productivities. We illustrated, tested, and validated the SMET method by analyzing two networks, a simple network for concept demonstration and an Escherichia coli metabolic network for aromatic amino acid overproduction. The SMET method could systematically predict simultaneous multiple enzyme targets and their optimized expression levels, consistent with experimental data from the literature, without performing an iterative sequence of single-enzyme perturbation. The SMET method was much more efficient and effective than single-enzyme perturbation in terms of computation time and finding improved solutions.

  10. Optimal design for an end face engagement worm gear with multiple worm-wheel meshing

    NASA Astrophysics Data System (ADS)

    Deng, Xingqiao; Zhu, Weibing; Chen, Yonghong; Chen, Shouan; Wang, Jinge

    2017-01-01

    To solve the problem for lacking a special mechanical transmission that could provide multiple outputs with high transmission efficiency and good lubrication in the modern industrial, a novel worm gear, named end face engagement worm gear, with multiple worm-wheel meshing is proposed for the first time. The essential parameters for the worm gear are optimized to enhance lubrication and meshing properties. Moreover, analysis of variance(ANOVA) is applied to determine the optimum levels and to determine the influence of parameters. The ANOVA results show that the novel end face engagement worm gear with multiple worm wheels provides high lubrication(the lubrication angle is more than 89°) and meshing performance(the induce normal curvature is less than 0.0002 mm-1). The interaction between center distance and roller slant distance most strongly influences the lubrication angle(contributed 51.6%), followed by the parameters of center distance(contributed 25.0%), roller slant distance(contributed 16.4%), tooth angle of gear, gear ratio, and roller radius. In addition, roller radius most strongly influences the induced normal curvature(contributed 39.4%), followed by roller slant distance(contributed 15.2%), tooth angle of the gear(contributed 9.0%), center distance, and gear ratio. The proposed worm gear helps to enrich the no-backlash high precision worm drive and the optimal design method can provide a useful reference on performance improvement of other worm gear.

  11. Design and Protocol of a Randomized Multiple Behavior Change Trial: Make Better Choices 2 (MBC2)

    PubMed Central

    Pellegrini, Christine A.; Steglitz, Jeremy; Johnston, Winter; Warnick, Jennifer; Adams, Tiara; McFadden, H.G.; Siddique, Juned; Hedeker, Donald; Spring, Bonnie

    2015-01-01

    Background Suboptimal diet and inactive lifestyle are among the most prevalent preventable causes of premature death. Interventions that target multiple behaviors are potentially efficient; however the optimal way to initiate and maintain multiple health behavior changes is unknown. Objective The Make Better Choices 2 (MBC2) trial aims to examine whether sustained healthful diet and activity change are best achieved by targeting diet and activity behaviors simultaneously or sequentially. Study Design Approximately 250 inactive adults with poor quality diet will be randomized to 3 conditions examining the best way to prescribe healthy diet and activity change. The 3 intervention conditions prescribe: 1) an increase in fruit and vegetable consumption (F/V+), decrease in sedentary leisure screen time (Sed−), and increase in physical activity (PA+) simultaneously (Simultaneous); 2) F/V+ and Sed− first, and then sequentially add PA+ (Sequential); or 3) Stress Management Control that addresses stress, relaxation, and sleep. All participants will receive a smartphone application to self-monitor behaviors and regular coaching calls to help facilitate behavior change during the 9 month intervention. Healthy lifestyle change in fruit/vegetable and saturated fat intakes, sedentary leisure screen time, and physical activity will be assessed at 3, 6, and 9 months. Significance MBC2 is a randomized m-Health intervention examining methods to maximize initiation and maintenance of multiple healthful behavior changes. Results from this trial will provide insight about an optimal technology supported approach to promote improvement in diet and physical activity. PMID:25625810

  12. Design and development of multiple emulsion for enhancement of oral bioavailability of acyclovir.

    PubMed

    Paul, Sumita; Kumar, Abhinesh; Yedurkar, Pramod; Sawant, Krutika

    2013-11-01

    The objective of this investigation was to design and develop water-in-oil-in-water type multiple emulsions (w/o/w emulsions) entrapping acyclovir for improving its oral bioavailability. Multiple emulsions (MEs) were prepared and optimized using Span-80 and Span-83 as lipophilic surfactant and Brij-35 as hydrophilic surfactant. The physio-chemical properties of the w/o/w emulsions - particle size, viscosity, phase separation (centrifugation test) and entrapment efficiency were measured and evaluated along with macroscopic and microscopic observations to confirm multiple nature, homogeneity and globule size. Stability study, in vitro and ex vivo release studies were performed followed by in vivo studies in rats. Stable w/o/w emulsions with a particle size of 33.098 ± 2.985 µm and 85.25 ± 4.865% entrapment efficiency were obtained. Stability studies showed that the concentration of lipophilic surfactant was very important for stability of MEs. Drug release from the prepared formulations showed initial rapid release followed by a much slower release. In vivo studies in rats indicated prolonged release and better oral bioavailability as compared to drug solution. The overall results of this study show the potential of the w/o/w emulsions as promising drug delivery systems for acyclovir.

  13. Design and protocol of a randomized multiple behavior change trial: Make Better Choices 2 (MBC2).

    PubMed

    Pellegrini, Christine A; Steglitz, Jeremy; Johnston, Winter; Warnick, Jennifer; Adams, Tiara; McFadden, H G; Siddique, Juned; Hedeker, Donald; Spring, Bonnie

    2015-03-01

    Suboptimal diet and inactive lifestyle are among the most prevalent preventable causes of premature death. Interventions that target multiple behaviors are potentially efficient; however the optimal way to initiate and maintain multiple health behavior changes is unknown. The Make Better Choices 2 (MBC2) trial aims to examine whether sustained healthful diet and activity change are best achieved by targeting diet and activity behaviors simultaneously or sequentially. Study design approximately 250 inactive adults with poor quality diet will be randomized to 3 conditions examining the best way to prescribe healthy diet and activity change. The 3 intervention conditions prescribe: 1) an increase in fruit and vegetable consumption (F/V+), decrease in sedentary leisure screen time (Sed-), and increase in physical activity (PA+) simultaneously (Simultaneous); 2) F/V+ and Sed- first, and then sequentially add PA+ (Sequential); or 3) Stress Management Control that addresses stress, relaxation, and sleep. All participants will receive a smartphone application to self-monitor behaviors and regular coaching calls to help facilitate behavior change during the 9 month intervention. Healthy lifestyle change in fruit/vegetable and saturated fat intakes, sedentary leisure screen time, and physical activity will be assessed at 3, 6, and 9 months. MBC2 is a randomized m-Health intervention examining methods to maximize initiation and maintenance of multiple healthful behavior changes. Results from this trial will provide insight about an optimal technology supported approach to promote improvement in diet and physical activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Research on the configuration design method of heterogeneous constellation reconstruction under the multiple objective and multiple constraint

    NASA Astrophysics Data System (ADS)

    Zhao, Shuang; Xu, Yanli; Dai, Huayu

    2017-05-01

    Aiming at the problem of configuration design of heterogeneous constellation reconstruction, a design method of heterogeneous constellation reconstruction based on multi objective and multi constraints is proposed. At first, the concept of heterogeneous constellation is defined. Secondly, the heterogeneous constellation reconstruction methods were analyzed, and then the two typical existing design methods of reconstruction, phase position uniformity method and reconstruction configuration design method based on optimization algorithm are summarized. The advantages and shortcomings of different reconstruction configuration design methods are compared, finally the heterogeneous constellation reconstruction configuration design is currently facing problems are analyzed and put forward the thinking about the reconstruction index system of heterogeneous constellation and the selection of optimal variables and the establishment of constraints in the optimization design of the configuration.

  15. Interrater Agreement on the Visual Analysis of Individual Tiers and Functional Relations in Multiple Baseline Designs.

    PubMed

    Wolfe, Katie; Seaman, Michael A; Drasgow, Erik

    2016-11-01

    Previous research on visual analysis has reported low levels of interrater agreement. However, many of these studies have methodological limitations (e.g., use of AB designs, undefined judgment task) that may have negatively influenced agreement. Our primary purpose was to evaluate whether agreement would be higher than previously reported if we addressed these weaknesses. Our secondary purposes were to investigate agreement at the tier level (i.e., the AB comparison) and at the functional relation level in multiple baseline designs and to examine the relationship between raters' decisions at each of these levels. We asked experts (N = 52) to make judgments about changes in the dependent variable in individual tiers and about the presence of an overall functional relation in 31 multiple baseline graphs. Our results indicate that interrater agreement was just at or just below minimally adequate levels for both types of decisions and that agreement at the individual tier level often resulted in agreement about the overall functional relation. We report additional findings and discuss implications for practice and future research. © The Author(s) 2016.

  16. Model observer design for detecting multiple abnormalities in anatomical background images

    NASA Astrophysics Data System (ADS)

    Wen, Gezheng; Markey, Mia K.; Park, Subok

    2016-03-01

    As psychophysical studies are resource-intensive to conduct, model observers are commonly used to assess and optimize medical imaging quality. Existing model observers were typically designed to detect at most one signal. However, in clinical practice, there may be multiple abnormalities in a single image set (e.g., multifocal and multicentric breast cancers (MMBC)), which can impact treatment planning. Prevalence of signals can be different across anatomical regions, and human observers do not know the number or location of signals a priori. As new imaging techniques have the potential to improve multiple-signal detection (e.g., digital breast tomosynthesis may be more effective for diagnosis of MMBC than planar mammography), image quality assessment approaches addressing such tasks are needed. In this study, we present a model-observer mechanism to detect multiple signals in the same image dataset. To handle the high dimensionality of images, a novel implementation of partial least squares (PLS) was developed to estimate different sets of efficient channels directly from the images. Without any prior knowledge of the background or the signals, the PLS channels capture interactions between signals and the background which provide discriminant image information. Corresponding linear decision templates are employed to generate both image-level and location-specific scores on the presence of signals. Our preliminary results show that the model observer using PLS channels, compared to our first attempts with Laguerre-Gauss channels, can achieve high performance with a reasonably small number of channels, and the optimal design of the model observer may vary as the tasks of clinical interest change.

  17. Designing a mixture experiment when the components are subject to a nonlinear multiple-component constraint

    SciTech Connect

    Piepel, Greg F.; Cooley, Scott K.; Vienna, John D.; Crum, Jarrod V.

    2015-12-14

    This article presents a case study of developing an experimental design for a constrained mixture experiment when the experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directly applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this article. The case study involves a 15-component nuclear waste glass example in which SO3 is one of the components. SO3 has a solubility limit in glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO3 solubility limit had previously been modeled by a partial quadratic mixture (PQM) model expressed in the relative proportions of the 14 other components. The PQM model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This article discusses the waste glass example and how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study.

  18. MPrime: efficient large scale multiple primer and oligonucleotide design for customized gene microarrays

    PubMed Central

    Rouchka, Eric C; Khalyfa, Abdelnaby; Cooper, Nigel GF

    2005-01-01

    Background Enhancements in sequencing technology have recently yielded assemblies of large genomes including rat, mouse, human, fruit fly, and zebrafish. The availability of large-scale genomic and genic sequence data coupled with advances in microarray technology have made it possible to study the expression of large numbers of sequence products under several different conditions in days where traditional molecular biology techniques might have taken months, or even years. Therefore, to efficiently study a number of gene products associated with a disease, pathway, or other biological process, it is necessary to be able to design primer pairs or oligonucleotides en masse rather than using a time consuming and laborious gene-by-gene method. Results We have developed an integrated system, MPrime, in order to efficiently calculate primer pairs or specific oligonucleotides for multiple genic regions based on a keyword, gene name, accession number, or sequence fasta format within the rat, mouse, human, fruit fly, and zebrafish genomes. A set of products created for mouse housekeeping genes from MPrime-designed primer pairs has been validated using both PCR-amplification and DNA sequencing. Conclusion These results indicate MPrime accurately incorporates standard PCR primer design characteristics to produce high scoring primer pairs for genes of interest. In addition, sequence similarity for a set of oligonucleotides constructed for the same set of genes indicates high specificity in oligo design. PMID:16014168

  19. Design for performance enhancement in feedback control systems with multiple saturating nonlinearities. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Kapasouris, Petros

    1988-01-01

    A systematic control design methodology is introduced for multi-input/multi-output systems with multiple saturations. The methodology can be applied to stable and unstable open loop plants with magnitude and/or rate control saturations and to systems in which state limitations are desired. This new methodology is a substantial improvement over previous heuristic single-input/single-output approaches. The idea is to introduce a supervisor loop so that when the references and/or disturbances are sufficiently small, the control system operates linearly as designed. For signals large enough to cause saturations, the control law is modified in such a way to ensure stability and to preserve, to the extent possible, the behavior of the linear control design. Key benefits of this methodology are: the modified compensator never produces saturating control signals, integrators and/or slow dynamics in the compensator never windup, the directional properties of the controls are maintained, and the closed loop system has certain guaranteed stability properties. The advantages of the new design methodology are illustrated by numerous simulations, including the multivariable longitudinal control of modified models of the F-8 (stable) and F-16 (unstable) aircraft.

  20. Controllable design of super-oscillatory lenses with multiple sub-diffraction-limit foci.

    PubMed

    Li, Muyuan; Li, Wenli; Li, Haoyong; Zhu, Yechuan; Yu, Yiting

    2017-05-02

    The conventional multifocal optical elements cannot precisely control the focal number, spot size, as well as the energy distribution in between. Here, the binary amplitude-type super-oscillatory lens (SOL) is utilized, and a robust and universal optimization method based on the vectorial angular spectrum (VAS) theory and the genetic algorithm (GA) is proposed, aiming to achieve the required focusing performance with arbitrary number of foci in preset energy distribution. Several typical designs of multifocal SOLs are demonstrated. Verified by the finite-difference time-domain (FDTD) numerical simulation, the designed multifocal SOLs agree well with the specific requirements. Moreover, the full-width at half-maximum (FWHM) of the achieved focal spots is close to λ/3 for all the cases (λ being the operating wavelength), which successfully breaks the diffraction limit. In addition, the designed SOLs are partially insensitive to the incident polarization state, functioning very well for both the linear polarization and circular polarization. The optimization method presented provides a useful design strategy for realizing a multiple sub-diffraction-limit foci field of SOLs. This research can find its potentials in such fields as parallel particle trapping and high-resolution microscopy imaging.

  1. Developing elementary teachers' ability to design and implement multiple representations of science content

    NASA Astrophysics Data System (ADS)

    Sheehan, Cheryl D.

    The purpose of this study was to investigate the effects of science instruction emphasizing multiple representations of science principles on elementary teachers' science knowledge, on their knowledge of how to use multiple representations in their science teaching practice, and the integration of this knowledge into pedagogical content knowledge. The overarching goal was to contribute to the on-going national debate on teacher quality. The study was exploratory using a mixed method, qualitative and quantitative, pre-test/post-test design. Multiple forms of data were collected including copies of all the participants' work products, detailed field notes taken during observations of the classes, and audio taped class and small group discussions. Changes in the teachers' science content knowledge, their ability to use multiple representations of science principles, and their ability to assess the appropriateness of the representations for teaching were measured over a fifteen week period of instruction in elementary science methods. Shulman's construct, pedagogical content knowledge (PCK), provided the framework for the study. Changes in the teachers' PCK were analyzed using Anderson's Schema Theory and Paivio's Duel Coding Theory. Participants' increased their use of science content knowledge, their ability to represent science principles in alternative ways, and their ability to explain the relationship between the principles and the representations. Their beliefs about how young children learn science did not change. The study illuminated the complexity of pedagogical content knowledge and how intellectually challenging it is to provide practicing elementary teachers with the kinds of experiences necessary to develop basic pedagogical content knowledge for the teaching of science.

  2. Controlled multiple growth factor delivery from bone tissue engineering scaffolds via designed affinity.

    PubMed

    Suárez-González, Darilis; Lee, Jae Sung; Diggs, Alisha; Lu, Yan; Nemke, Brett; Markel, Mark; Hollister, Scott J; Murphy, William L

    2014-08-01

    It is known that angiogenesis plays an important role in bone regeneration and that release of angiogenic and osteogenic growth factors can enhance bone formation. Multiple growth factors play key roles in processes that lead to tissue formation/regeneration during natural tissue development and repair. Therefore, treatments aiming to mimic tissue regeneration can benefit from multiple growth factor release, and there remains a need for simple clinically relevant approaches for dual growth factor release. We hypothesized that mineral coatings could be used as a platform for controlled incorporation and release of multiple growth factors. Specifically, mineral-coated scaffolds were "dip coated" in multiple growth factor solutions, and growth factor binding and release were dictated by the growth factor-mineral binding affinity. Beta tricalcium phosphate (β-TCP) scaffolds were fabricated using indirect solid-free form fabrication techniques and coated with a thin conformal mineral layer. Mineral-coated β-TCP scaffolds were sequentially dipped in recombinant human vascular endothelial growth factor (rhVEGF) and a modular bone morphogenetic peptide, a mineral-binding version of bone morphogenetic protein 2 (BMP2), solutions to allow for the incorporation of each growth factor. The dual release profile showed sustained release of both growth factors for over more than 60 days. Scaffolds releasing either rhVEGF alone or the combination of growth factors showed an increase in blood vessel ingrowth in a dose-dependent manner in a sheep intramuscular implantation model. This approach demonstrates a "modular design" approach, in which a controllable biologics carrier is integrated into a structural scaffold as a thin surface coating.

  3. Multiple harmonic frequencies resonant cavity design and half-scale prototype measurements for a fast kicker

    DOE PAGES

    Huang, Yulu; Wang, Haipeng; Wang, Shaoheng; ...

    2016-12-09

    Quarter wavelength resonator (QWR) based deflecting cavities with the capability of supporting multiple odd-harmonic modes have been developed for an ultrafast periodic kicker system in the proposed Jefferson Lab Electron Ion Collider (JLEIC, formerly MEIC). Previous work on the kicking pulse synthesis and the transverse beam dynamics tracking simulations show that a flat-top kicking pulse can be generated with minimal emittance growth during injection and circulation of the cooling electron bunches. This flat-top kicking pulse can be obtained when a DC component and 10 harmonic modes with appropriate amplitude and phase are combined together. To support 10 such harmonic modes,more » four QWR cavities are used with 5, 3, 1, and 1 modes, respectively. In the multiple-mode cavities, several slightly tapered segments of the inner conductor are introduced to tune the higher order deflecting modes to be harmonic, and stub tuners are used to fine tune each frequency to compensate for potential errors. In this paper, we summarize the electromagnetic design of the five-mode cavity, including the geometry optimization to get high transverse shunt impedance, the frequency tuning and sensitivity analysis, and the single loop coupler design for coupling to all of the harmonic modes. In particular we report on the design and fabrication of a half-scale copper prototype of this proof-of-principle five-odd-mode cavity, as well as the rf bench measurements. Lastly, we demonstrate mode superposition in this cavity experimentally, which illustrates the kicking pulse generation concept.« less

  4. An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays.

    PubMed

    Manservisi, Fabiana; Marquillas, Clara Babot; Buscaroli, Annalisa; Huff, James; Lauriola, Michelina; Mandrioli, Daniele; Manservigi, Marco; Panzacchi, Simona; Silbergeld, Ellen K; Belpoggi, Fiorella

    2017-03-01

    For nearly five decades long-term studies in rodents have been the accepted benchmark for assessing chronic long-term toxic effects, particularly carcinogenicity, of chemicals. The European Food Safety Authority (EFSA) and the World Health Organization (WHO) have pointed out that the current set of internationally utilized test methods capture only some of the potential adverse effects associated with exposures to these agents over the lifetime. In this paper, we propose the adaption of the carcinogenicity bioassay to integrate additional protocols for comprehensive long-term toxicity assessment that includes developmental exposures and long-term outcomes, capable of generating information on a broad spectrum of different end points. An integrated study design based on a stepwise process is described that includes the priority end points of the Economic Co-operation and Development and the National Toxicology Program guidelines on carcinogenicity and chronic toxicity and developmental and reproductive toxicity. Integrating a comprehensive set of relevant toxicological end points in a single protocol represents an opportunity to optimize animal use in accordance with the 3Rs (replacement, reduction and refinement). This strategy has the potential to provide sufficient data on multiple windows of susceptibility of specific interest for risk assessments and public health decision-making by including prenatal, lactational, neonatal exposures and evaluating outcomes over the lifespan. This integrated study design is efficient in that the same generational cohort of rats used for evaluating long-term outcomes can be monitored in satellite parallel experiments to measure biomarkers and other parameters related to system-specific responses including metabolic alterations and endocrine disturbances. Citation: Manservisi F, Babot Marquillas C, Buscaroli A, Huff J, Lauriola M, Mandrioli D, Manservigi M, Panzacchi S, Silbergeld EK, Belpoggi F. 2017. An integrated experimental

  5. An Integrated Experimental Design for the Assessment of Multiple Toxicological End Points in Rat Bioassays

    PubMed Central

    Manservisi, Fabiana; Marquillas, Clara Babot; Buscaroli, Annalisa; Huff, James; Lauriola, Michelina; Mandrioli, Daniele; Manservigi, Marco; Panzacchi, Simona; Silbergeld, Ellen K.; Belpoggi, Fiorella

    2016-01-01

    Background: For nearly five decades long-term studies in rodents have been the accepted benchmark for assessing chronic long-term toxic effects, particularly carcinogenicity, of chemicals. The European Food Safety Authority (EFSA) and the World Health Organization (WHO) have pointed out that the current set of internationally utilized test methods capture only some of the potential adverse effects associated with exposures to these agents over the lifetime. Objectives: In this paper, we propose the adaption of the carcinogenicity bioassay to integrate additional protocols for comprehensive long-term toxicity assessment that includes developmental exposures and long-term outcomes, capable of generating information on a broad spectrum of different end points. Discussion: An integrated study design based on a stepwise process is described that includes the priority end points of the Economic Co-operation and Development and the National Toxicology Program guidelines on carcinogenicity and chronic toxicity and developmental and reproductive toxicity. Integrating a comprehensive set of relevant toxicological end points in a single protocol represents an opportunity to optimize animal use in accordance with the 3Rs (replacement, reduction and refinement). This strategy has the potential to provide sufficient data on multiple windows of susceptibility of specific interest for risk assessments and public health decision-making by including prenatal, lactational, neonatal exposures and evaluating outcomes over the lifespan. Conclusion: This integrated study design is efficient in that the same generational cohort of rats used for evaluating long-term outcomes can be monitored in satellite parallel experiments to measure biomarkers and other parameters related to system-specific responses including metabolic alterations and endocrine disturbances. Citation: Manservisi F, Babot Marquillas C, Buscaroli A, Huff J, Lauriola M, Mandrioli D, Manservigi M, Panzacchi S, Silbergeld

  6. Design of eight-mode polarization-maintaining few-mode fiber for multiple-input multiple-output-free spatial division multiplexing.

    PubMed

    Wang, Lixian; LaRochelle, Sophie

    2015-12-15

    We propose a polarization-maintaining few-mode fiber (FMF) that features an elliptical ring shaped core with a high refractive index contrast ∼0.03 between the core and the cladding. This fiber design alleviates the usual trade-off between the number of guided modes and the achievable birefringence that is usually observed in conventional elliptical-core FMFs. Through numerical simulations, we show that this fiber design can support up to 10 guided vector modes over the entire C band while providing large birefringence. Except for the two fundamental modes, the eight higher-order vector modes are all separated from their adjacent modes by effective index differences >10⁻⁴, which is the typical birefringence value of single-mode polarization maintaining fibers. The designed fiber targets applications in spatial division multiplexing of optical channels, without multiple-input-multiple-output (MIMO) digital signal processing, for short-reach optical interconnects.

  7. Formation tracker design of multiple mobile robots with wheel perturbations: adaptive output-feedback approach

    NASA Astrophysics Data System (ADS)

    Yoo, Sung Jin

    2016-11-01

    This paper presents a theoretical design approach for output-feedback formation tracking of multiple mobile robots under wheel perturbations. It is assumed that these perturbations are unknown and the linear and angular velocities of the robots are unmeasurable. First, adaptive state observers for estimating unmeasurable velocities of the robots are developed under the robots' kinematics and dynamics including wheel perturbation effects. Then, we derive a virtual-structure-based formation tracker scheme according to the observer dynamic surface design procedure. The main difficulty of the output-feedback control design is to manage the coupling problems between unmeasurable velocities and unknown wheel perturbation effects. These problems are avoided by using the adaptive technique and the function approximation property based on fuzzy logic systems. From the Lyapunov stability analysis, it is shown that point tracking errors of each robot and synchronisation errors for the desired formation converge to an adjustable neighbourhood of the origin, while all signals in the controlled closed-loop system are semiglobally uniformly ultimately bounded.

  8. A multi-plate velocity-map imaging design for high-resolution photoelectron spectroscopy.

    PubMed

    Kregel, Steven J; Thurston, Glen K; Zhou, Jia; Garand, Etienne

    2017-09-07

    A velocity map imaging (VMI) setup consisting of multiple electrodes with three adjustable voltage parameters, designed for slow electron velocity map imaging applications, is presented. The motivations for this design are discussed in terms of parameters that influence the VMI resolution and functionality. Particularly, this VMI has two tunable potentials used to adjust for optimal focus, yielding good VMI focus across a relatively large energy range. It also allows for larger interaction volumes without significant sacrifice to the resolution via a smaller electric gradient at the interaction region. All the electrodes in this VMI have the same dimensions for practicality and flexibility, allowing for relatively easy modifications to suit different experimental needs. We have coupled this VMI to a cryogenic ion trap mass spectrometer that has a flexible source design. The performance is demonstrated with the photoelectron spectra of S(-) and CS2(-). The latter has a long vibrational progression in the ground state, and the temperature dependence of the vibronic features is probed by changing the temperature of the ion trap.

  9. A multi-plate velocity-map imaging design for high-resolution photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Kregel, Steven J.; Thurston, Glen K.; Zhou, Jia; Garand, Etienne

    2017-09-01

    A velocity map imaging (VMI) setup consisting of multiple electrodes with three adjustable voltage parameters, designed for slow electron velocity map imaging applications, is presented. The motivations for this design are discussed in terms of parameters that influence the VMI resolution and functionality. Particularly, this VMI has two tunable potentials used to adjust for optimal focus, yielding good VMI focus across a relatively large energy range. It also allows for larger interaction volumes without significant sacrifice to the resolution via a smaller electric gradient at the interaction region. All the electrodes in this VMI have the same dimensions for practicality and flexibility, allowing for relatively easy modifications to suit different experimental needs. We have coupled this VMI to a cryogenic ion trap mass spectrometer that has a flexible source design. The performance is demonstrated with the photoelectron spectra of S- and CS2 -. The latter has a long vibrational progression in the ground state, and the temperature dependence of the vibronic features is probed by changing the temperature of the ion trap.

  10. Cognitive and psychomotor performance tests and experiment design in multiple chemical sensitivity.

    PubMed Central

    Wetherell, A

    1997-01-01

    People suffering from multiple chemical sensitivity (MCS) complain of a variety of symptoms that could impair cognitive and psychomotor function either directly or indirectly. This paper discusses the use of cognitive and psychomotor performance tests together with some experiment designs that could be considered for use to assess fitness of MCS sufferers for work or the efficacy of diagnostic, preventative, or therapeutic measures. The tests could also contribute to the body of objective information on MCS and help sway the opinion of those who are dubious of its authenticity. The credentials of cognitive and psychomotor performance tests are derived from their successful use in studying the effects of drugs, and the types of tests are illustrated by describing those used by the United Kingdom Defence Evaluation and Research Agency Chemical and Biological Defence Human Studies Group, which has been involved in the assessment of drugs and chemicals on work performance for many years. The tests include mathematical, verbal and spatial processing, tracking, reaction time, attention and vigilance, and memory tests. The discussion of experiment designs includes both repeated measures and parallel groups designs together with their advantages and disadvantages and some suggested modifications to accommodate the particular problems posed by MCS. PMID:9167986

  11. Increased statistical power with combined independent randomization tests used with multiple-baseline design.

    PubMed

    Tyrrell, Pascal N; Corey, Paul N; Feldman, Brian M; Silverman, Earl D

    2013-06-01

    Physicians often assess the effectiveness of treatments on a small number of patients. Multiple-baseline designs (MBDs), based on the Wampold-Worsham (WW) method of randomization and applied to four subjects, have relatively low power. Our objective was to propose another approach with greater power that does not suffer from the time requirements of the WW method applied to a greater number of subjects. The power of a design that involves the combination of two four-subject MBDs was estimated using computer simulation and compared with the four- and eight-subject designs. The effect of a delayed linear response to treatment on the power of the test was also investigated. Power was found to be adequate (>80%) for a standardized mean difference (SMD) greater than 0.8. The effect size associated with 80% power from combined tests was smaller than that of the single four-subject MBD (SMD=1.3) and comparable with the eight-subject MBD (SMD=0.6). A delayed linear response to the treatment resulted in important reductions in power (20-35%). By combining two four-subject MBD tests, an investigator can detect better effect sizes (SMD=0.8) and be able to complete a comparatively timelier and feasible study. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Designing a Pilot Sequential Multiple Assignment Randomized Trial for Developing an Adaptive Treatment Strategy

    PubMed Central

    Almirall, Daniel; Compton, Scott N.; Gunlicks-Stoessel, Meredith; Duan, Naihua; Murphy, Susan A.

    2012-01-01

    There is growing interest in how best to adapt and re-adapt treatments to individuals to maximize clinical benefit. In response, adaptive treatment strategies (ATS), which operationalize adaptive, sequential clinical decision making, have been developed. From a patient's perspective an ATS is a sequence of treatments, each individualized to the patient's evolving health status. From a clinician's perspective, an ATS is a sequence of decision rules that input the patient's current health status and output the next recommended treatment. Sequential multiple assignment randomized trials (SMART) have been developed to address the sequencing questions that arise in the development of ATSs, but SMARTs are relatively new in clinical research. This article provides an introduction to ATSs and SMART designs. This article also discusses the design of SMART pilot studies to address feasibility concerns, and to prepare investigators for a full-scale SMART. As an example, we consider an example SMART for the development of an ATS in the treatment of pediatric generalized anxiety disorders. Using the example SMART, we identify and discuss design issues unique to SMARTs that are best addressed in an external pilot study prior to the full-scale SMART. We also address the question of how many participants are needed in a SMART pilot study. A properly executed pilot study can be used to effectively address concerns about acceptability and feasibility in preparation for (that is, prior to) executing a full-scale SMART. PMID:22438190

  13. Designing a pilot sequential multiple assignment randomized trial for developing an adaptive treatment strategy.

    PubMed

    Almirall, Daniel; Compton, Scott N; Gunlicks-Stoessel, Meredith; Duan, Naihua; Murphy, Susan A

    2012-07-30

    There is growing interest in how best to adapt and readapt treatments to individuals to maximize clinical benefit. In response, adaptive treatment strategies (ATS), which operationalize adaptive, sequential clinical decision making, have been developed. From a patient's perspective an ATS is a sequence of treatments, each individualized to the patient's evolving health status. From a clinician's perspective, an ATS is a sequence of decision rules that input the patient's current health status and output the next recommended treatment. Sequential multiple assignment randomized trials (SMART) have been developed to address the sequencing questions that arise in the development of ATSs, but SMARTs are relatively new in clinical research. This article provides an introduction to ATSs and SMART designs. This article also discusses the design of SMART pilot studies to address feasibility concerns, and to prepare investigators for a full-scale SMART. We consider an example SMART for the development of an ATS in the treatment of pediatric generalized anxiety disorders. Using the example SMART, we identify and discuss design issues unique to SMARTs that are best addressed in an external pilot study prior to the full-scale SMART. We also address the question of how many participants are needed in a SMART pilot study. A properly executed pilot study can be used to effectively address concerns about acceptability and feasibility in preparation for (that is, prior to) executing a full-scale SMART. Copyright © 2012 John Wiley & Sons, Ltd.

  14. An Extended Mission to Multiple Asteroid Flybys after Lunar Exploration: Design and analysis

    NASA Astrophysics Data System (ADS)

    Dong, Qiao; Pingyuan, Cui; Hutao, Cui

    Asteroids are key objects for the research of the origin and evolution of the solar system, because they relatively well conserve their past, as they are often said to be the fossil from the early phase of the solar system. Human have carried out many small celestial body missions (such as DS-I, NEAR, Stardust, Deep impact, etc) and gained a plenty of valuable experience. With many new asteroid or comet missions in various stages of development (Dawn, ROSETTA, Hayabusa-II), the situation regarding our understanding of these bodies can improve in the future. With the success of "Chang-Er" program for lunar exploration and the development of "Ying-Huo" program for Mars exploration, it will provide the great opportunity for Chinese development of the deep space exploration. Following up the "Chang-Er" and "Ying-Huo" program, two promising scenarios have been discussed. One of them is a multiple asteroid rendezvous and sample return mission aiming at several spectral known Near-Earth asteroids. The other is a multiple asteroid flyby mission which is an extended "Chang-Er" mission for lunar exploration. Here, an extended mission to multiple asteroid flybys after lunar exploration is proposed and discussed. We investigated feasible mission scenarios. According to the constraints of the mission, we search and present the optimal rendezvous and flyby opportunities for potential asteroids. The preliminary design results of the proposed missions will be reported. Finally, we analyze the trajectory characteristics and gave some key parameters, which would have a direct impact on communication system, power system, thermal control system of spacecraft and the optical instrument for science mission etc.

  15. A Modified Uniform Cramer–Rao Bound for Multiple Pinhole Aperture Design

    PubMed Central

    Meng, L. J.; Clinthorne, N. H.

    2016-01-01

    This paper presents a modified Uniform Cramer–Rao bound (UCRB) for studying estimator spatial resolution and variance tradeoffs. We proposed to use a resolution constraint that is imposed on mean gradient vectors of achieved estimators and derived the minimum achievable variance for any estimator satisfies this resolution constraint. This approach partially overcomes the limitations of the former UCRB approach based on a bias-gradient norm constraint. We applied this method in a feasibility study of using multiple pinhole apertures for small animal SPECT imaging applications. The SPECT system studied was based on an existing gamma camera. The achievable spatial resolution and variance tradeoffs for systems with different design parameters, such as number of pinholes and pinhole size, were studied. PMID:15250642

  16. Conceptual design of a multiple cable crane for planetary surface operations

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Yang, Li-Farn

    1991-01-01

    A preliminary design study is presented of a mobile crane suitable for conducting remote, automated construction operations on planetary surfaces. A cursory study was made of earth based mobile cranes and the needs for major improvements were identified. Current earth based cranes have a single cable supporting the payload, and precision positioning is accomplished by the use of construction workers controlling the payload by the use of tethers. For remote, autonomous operations on planetary surfaces it will be necessary to perform the precision operations without the use of humans. To accomplish this the payload must be stabilized relative to the crane. One approach for accomplishing this is to suspend the payload on multiple cable. A 3-cable suspension system crane concept is discussed. An analysis of the natural frequency of the system is presented which verifies the legitimacy of the concept.

  17. Design of superbasic guanidines: the role of multiple intramolecular hydrogen bonds.

    PubMed

    Barić, Danijela; Dragičević, Ivan; Kovačević, Borislav

    2013-04-19

    New organic superbases have been designed using the concept of multiple intramolecular hydrogen bonds. Substituents capable of forming strong intramolecular H-bonds were selected on the basis of the energy of stabilization that occurs upon the formation of a complex between N,N',N"-trimethylguanidine and small model molecules. The proton affinities and the corresponding pK(a) values in acetonitrile of the new superbases are examined by Density Functional Theory (DFT). It is shown that N,N',N"-substitution of guanidine with appropriate substituents results in new organic superbases with gas phase proton affinities between 286 and 293 kcal mol(-1), thus being 15 to 20 kcal mol(-1) more basic than parental superbase N,N',N"-tris[(3-dimethylamino)propyl]-guanidine (tris-DMPG), whereas estimated pK(a) values in acetonitrile range between 29.5 and 33.2.

  18. Multidisciplinary Design Optimization of a Morphing Wingtip Concept with Multiple Morphing Stages at Cruise

    NASA Astrophysics Data System (ADS)

    Leahy, Michael

    Morphing an aircraft wingtip can provide substantial performance improvement. Most civil transport aircraft are optimized for range but for other flight conditions such as take-off and climb they are used as constraints. These constraints could potentially reduce the performance of an aircraft at cruise. By altering the shape of the wingtip, we can force the load distribution to adapt to the required flight condition to improve performance. Using a Variable Geometry Truss Mechanism (VGTM) concept to morph the wingtip of an aircraft with a Multidisciplinary Design Optimization (MDO) framework, the current work will attempt to find an optimal wing and wingtip shape to minimize fuel consumption for multiple morphing stages during cruise. This optimization routine was conducted with a Particle Swarm Optimization (PSO) algorithm using different fidelity tools to analyze the aerodynamic and structural disciplines.

  19. Driving modes for designing the cornering response of fully electric vehicles with multiple motors

    NASA Astrophysics Data System (ADS)

    De Novellis, Leonardo; Sorniotti, Aldo; Gruber, Patrick

    2015-12-01

    Fully electric vehicles with multiple drivetrains allow a significant variation of the steady-state and transient cornering responses through the individual control of the electric motor drives. As a consequence, alternative driving modes can be created that provide the driver the option to select the preferred dynamic vehicle behavior. This article presents a torque-vectoring control structure based on the combination of feedforward and feedback contributions for the continuous control of vehicle yaw rate. The controller is specifically developed to be easily implementable on real-world vehicles. A novel model-based procedure for the definition of the control objectives is described in detail, together with the automated tuning process of the algorithm. The implemented control functions are demonstrated with experimental vehicle tests. The results show the possibilities of torque-vectoring control in designing the vehicle understeer characteristic.

  20. Design of a datapath for single-flux-quantum microprocessors with multiple ALUs

    NASA Astrophysics Data System (ADS)

    Tanaka, M.; Kondo, T.; Kawamoto, T.; Kamiya, Y.; Fujiwara, K.; Yamanashi, Y.; Akimoto, A.; Fujimaki, A.; Yoshikawa, N.; Terai, H.; Yorozu, S.

    2005-10-01

    We have demonstrated the components of datapath toward single-flux-quantum microprocessors based on our new architecture called the forwarding architecture. In the forwarding architecture, we improve the performance by utilizing multiple ALUs to conceal the inefficiency of bit-serial processing. The key components of the datapath are a register file and cascaded ALUs. We have designed the register file to hold four bit-serial data with two read ports and one write port. In each ALU, we have implemented six functionalities: addition, subtraction, logical AND, OR and Exclusive OR operations, and comparison with zero. We have tested the register file and the ALU using high-speed on-chip testing, and confirmed the correct operations up to 18 GHz and 23 GHz, respectively.

  1. Design of a LQR Controller of Reduced Inputs for Multiple Spacecraft Formation Flying

    NASA Technical Reports Server (NTRS)

    Starin, Scott R.; Yedavalli, R. K.; Sparks, Andrew G.; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    Regarding multiple spacecraft formation flying, the observation is made that control thrust need only be applied coplanar to the local horizon to achieve complete controllability of a two-satellite formation. Without the need for zenith-nadir (radial) thrust, simplifications and reduction of the weight of the propulsion system may be accomplished. This work focuses on the validation of this radial-excluding control system on its own merits, and in comparison to a related system which does provide thrust parallel to the orbital radius. Simulations are performed using commercial ODE solvers to propagate the Keplerian dynamics of a controlled satellite relative to an uncontrolled, leader satellite. The conclusion is drawn that, despite the exclusion of the radial thrust axis, the remaining control thrust available still provides enough control to design a gain matrix of adequate performance using linear-quadratic regulator (LQR) techniques.

  2. Studies with staggered starts: multiple baseline designs and group-randomized trials.

    PubMed

    Rhoda, Dale A; Murray, David M; Andridge, Rebecca R; Pennell, Michael L; Hade, Erinn M

    2011-11-01

    Multiple baseline designs (MBDs) have been suggested as alternatives to group-randomized trials (GRT). We reviewed structural features of MBDs and considered their potential effectiveness in public health research. We also reviewed the effect of staggered starts on statistical power. We reviewed the MBD literature to identify key structural features, recent suggestions that MBDs be adopted in public health research, and the literature on power in GRTs with staggered starts. We also computed power for MBDs and GRTs. The features that have contributed to the success of small MBDs in some fields are not likely to translate well to public health research. MBDs can be more powerful than GRTs under some conditions, but those conditions involve assumptions that require careful evaluation in practice. MBDs will often serve better as a complement of rather than as an alternative to GRTs. GRTs may employ staggered starts for logistical or ethical reasons, but this will always increase their duration and will often increase their cost.

  3. Logistics system design for biomass-to-bioenergy industry with multiple types of feedstocks.

    PubMed

    Zhu, Xiaoyan; Yao, Qingzhu

    2011-12-01

    It is technologically possible for a biorefinery to use a variety of biomass as feedstock including native perennial grasses (e.g., switchgrass) and agricultural residues (e.g., corn stalk and wheat straw). Incorporating the distinct characteristics of various types of biomass feedstocks and taking into account their interaction in supplying the bioenergy production, this paper proposed a multi-commodity network flow model to design the logistics system for a multiple-feedstock biomass-to-bioenergy industry. The model was formulated as a mixed integer linear programming, determining the locations of warehouses, the size of harvesting team, the types and amounts of biomass harvested/purchased, stored, and processed in each month, the transportation of biomass in the system, and so on. This paper demonstrated the advantages of using multiple types of biomass feedstocks by comparing with the case of using a single feedstock (switchgrass) and analyzed the relationship of the supply capacity of biomass feedstocks to the output and cost of biofuel.

  4. Design, testing and two-dimensional flow modeling of a multiple-disk fan

    SciTech Connect

    Engin, Tahsin; Oezdemir, Mustafa; Cesmeci, Sevki

    2009-11-15

    A multiple-disk Tesla type fan has been designed, tested and analyzed two-dimensionally using the conservation of angular momentum principle. Experimental results showed that such multiple-disk fans exhibited exceptionally low performance characteristics, which could be attributed to the low viscosity, tangential nature of the flow, and large mechanical energy losses at both suction and discharge sections that are comparable to the total input power. By means of theoretical analysis, local and overall shearing stresses on the disk surfaces have been determined based on tangential and radial velocity distributions of the air flow of different volume flow rates at prescribed disk spaces and rotational speeds. Then the total power transmitted by rotating disks to air flow, and the power acquired by the air flow in the gap due to transfer of angular momentum have been obtained by numerically integrating shearing stresses over the disk surfaces. Using the measured shaft and hydraulic powers, these quantities were utilized to evaluate mechanical energy losses associated with the suction and discharge sections of the fan. (author)

  5. Multiple imputation of missing data in multilevel designs: A comparison of different strategies.

    PubMed

    Lüdtke, Oliver; Robitzsch, Alexander; Grund, Simon

    2017-03-01

    Multiple imputation is a widely recommended means of addressing the problem of missing data in psychological research. An often-neglected requirement of this approach is that the imputation model used to generate the imputed values must be at least as general as the analysis model. For multilevel designs in which lower level units (e.g., students) are nested within higher level units (e.g., classrooms), this means that the multilevel structure must be taken into account in the imputation model. In the present article, we compare different strategies for multiply imputing incomplete multilevel data using mathematical derivations and computer simulations. We show that ignoring the multilevel structure in the imputation may lead to substantial negative bias in estimates of intraclass correlations as well as biased estimates of regression coefficients in multilevel models. We also demonstrate that an ad hoc strategy that includes dummy indicators in the imputation model to represent the multilevel structure may be problematic under certain conditions (e.g., small groups, low intraclass correlations). Imputation based on a multivariate linear mixed effects model was the only strategy to produce valid inferences under most of the conditions investigated in the simulation study. Data from an educational psychology research project are also used to illustrate the impact of the various multiple imputation strategies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Experimental factorial design applied to mucoadhesive lipid nanoparticles via multiple emulsion process.

    PubMed

    Fangueiro, Joana F; Andreani, Tatiana; Egea, Maria A; Garcia, Maria L; Souto, Selma B; Souto, Eliana B

    2012-12-01

    Solid lipid nanoparticles (SLNs) produced from multiple emulsions technology theoretically enclose an inner aqueous compartment suitable for hydrophilic biomolecules. This paper reports a 3(3) full factorial design study to optimize SLNs formulations for hydrophilic biomolecules. The concentrations of solid lipid, lipophilic and hydrophilic emulsifiers were set as the 3 independent variables. Mean particle size (Z-Ave), polydispersity index (PI) and zeta potential (ZP) were set as the dependent variables. The selected optimized parameters were set as 1.0 wt% of solid lipid, 0.25 wt% of lipophilic emulsifier and 1.5 wt% of hydrophilic emulsifier. The coating of SLNs with sodium alginate was found to improve the ZP of the lipid particles and these results suggest that the ideal concentration was 0.75 wt%. The influence of low pH (i.e., about 2-3) in the inner aqueous phase was stronger than higher pH values, contributing for the production of larger droplet sizes. Nevertheless, these systems can be useful for the incorporation of biomolecules requiring a pH ranging between 4 and 10. SLNs based on multiple emulsions technology were found to be a promising approach for the incorporation of several hydrophilic drugs, such as proteins and peptides. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Concurrent airline fleet allocation and aircraft design with profit modeling for multiple airlines

    NASA Astrophysics Data System (ADS)

    Govindaraju, Parithi

    A "System of Systems" (SoS) approach is particularly beneficial in analyzing complex large scale systems comprised of numerous independent systems -- each capable of independent operations in their own right -- that when brought in conjunction offer capabilities and performance beyond the constituents of the individual systems. The variable resource allocation problem is a type of SoS problem, which includes the allocation of "yet-to-be-designed" systems in addition to existing resources and systems. The methodology presented here expands upon earlier work that demonstrated a decomposition approach that sought to simultaneously design a new aircraft and allocate this new aircraft along with existing aircraft in an effort to meet passenger demand at minimum fleet level operating cost for a single airline. The result of this describes important characteristics of the new aircraft. The ticket price model developed and implemented here enables analysis of the system using profit maximization studies instead of cost minimization. A multiobjective problem formulation has been implemented to determine characteristics of a new aircraft that maximizes the profit of multiple airlines to recognize the fact that aircraft manufacturers sell their aircraft to multiple customers and seldom design aircraft customized to a single airline's operations. The route network characteristics of two simple airlines serve as the example problem for the initial studies. The resulting problem formulation is a mixed-integer nonlinear programming problem, which is typically difficult to solve. A sequential decomposition strategy is applied as a solution methodology by segregating the allocation (integer programming) and aircraft design (non-linear programming) subspaces. After solving a simple problem considering two airlines, the decomposition approach is then applied to two larger airline route networks representing actual airline operations in the year 2005. The decomposition strategy serves

  8. Psychological treatment of reported sleep disorder in adults with intellectual disability using a multiple baseline design.

    PubMed

    Gunning, M J; Espie, C A

    2003-03-01

    The literature on sleep disturbance in adults with intellectual disability (ID) is sparse. Although prevalence rates for sleep disorders appear similar to those of non-disabled populations, previous treatment studies have largely been comprised of uncontrolled cases. Therefore, the present study adopted a single-case experimental methodology to evaluate behavioural sleep intervention. A screening questionnaire was posted to 384 adults with ID and the sleep pattern of respondents with possible sleep disorders was further assessed using a structured diagnostic schedule. From the sleep-disordered subgroup, 12 participants were selected for a 4-week behavioural sleep intervention that was evaluated using randomly allocated, multiple-baseline, across-subjects designs and within-subject interrupted time series analyses (ITSAs). A total of 155 adults with ID (83 females and 72 males; mean age = 32 years, SD = 16.5 years), or their carers, completed the questionnaire (return rate = 40%). The application of sleep diagnostic criteria revealed that 17% had clinically significant difficulty getting to sleep and 11% had difficulty remaining asleep. Nine out of the 12 participants recruited for the intervention completed all the experimental phases, thus providing three sets of three multiple-baseline designs. Visual inspection of within- and between-subject effects suggested beneficial treatment-specific effects across a range of target variables. The ITSA confirmed significant effects (P < 0.05) or trends (P < 0.10) for six out of the nine participants. Behavioural sleep management may improve sleep pattern or sleep-related functioning in the majority of adults with ID who have significant sleep problems. The single-case methodology is helpful in addressing the heterogeneity of individual presentation, although clinical trial methodology is required to confirm these findings on a larger scale.

  9. MRMaid, the web-based tool for designing multiple reaction monitoring (MRM) transitions.

    PubMed

    Mead, Jennifer A; Bianco, Luca; Ottone, Vanessa; Barton, Chris; Kay, Richard G; Lilley, Kathryn S; Bond, Nicholas J; Bessant, Conrad

    2009-04-01

    Multiple reaction monitoring (MRM) of peptides uses tandem mass spectrometry to quantify selected proteins of interest, such as those previously identified in differential studies. Using this technique, the specificity of precursor to product transitions is harnessed for quantitative analysis of multiple proteins in a single sample. The design of transitions is critical for the success of MRM experiments, but predicting signal intensity of peptides and fragmentation patterns ab initio is challenging given existing methods. The tool presented here, MRMaid (pronounced "mermaid") offers a novel alternative for rapid design of MRM transitions for the proteomics researcher. The program uses a combination of knowledge of the properties of optimal MRM transitions taken from expert practitioners and literature with MS/MS evidence derived from interrogation of a database of peptide identifications and their associated mass spectra. The tool also predicts retention time using a published model, allowing ordering of transition candidates. By exploiting available knowledge and resources to generate the most reliable transitions, this approach negates the need for theoretical prediction of fragmentation and the need to undertake prior "discovery" MS studies. MRMaid is a modular tool built around the Genome Annotating Proteomic Pipeline framework, providing a web-based solution with both descriptive and graphical visualizations of transitions. Predicted transition candidates are ranked based on a novel transition scoring system, and users may filter the results by selecting optional stringency criteria, such as omitting frequently modified residues, constraining the length of peptides, or omitting missed cleavages. Comparison with published transitions showed that MRMaid successfully predicted the peptide and product ion pairs in the majority of cases with appropriate retention time estimates. As the data content of the Genome Annotating Proteomic Pipeline repository increases

  10. Developing Multiple Diverse Potential Designs for Heat Transfer Utilizing Graph Based Evolutionary Algorithms

    SciTech Connect

    David J. Muth Jr.

    2006-09-01

    This paper examines the use of graph based evolutionary algorithms (GBEAs) to find multiple acceptable solutions for heat transfer in engineering systems during the optimization process. GBEAs are a type of evolutionary algorithm (EA) in which a topology, or geography, is imposed on an evolving population of solutions. The rates at which solutions can spread within the population are controlled by the choice of topology. As in nature geography can be used to develop and sustain diversity within the solution population. Altering the choice of graph can create a more or less diverse population of potential solutions. The choice of graph can also affect the convergence rate for the EA and the number of mating events required for convergence. The engineering system examined in this paper is a biomass fueled cookstove used in developing nations for household cooking. In this cookstove wood is combusted in a small combustion chamber and the resulting hot gases are utilized to heat the stove’s cooking surface. The spatial temperature profile of the cooking surface is determined by a series of baffles that direct the flow of hot gases. The optimization goal is to find baffle configurations that provide an even temperature distribution on the cooking surface. Often in engineering, the goal of optimization is not to find the single optimum solution but rather to identify a number of good solutions that can be used as a starting point for detailed engineering design. Because of this a key aspect of evolutionary optimization is the diversity of the solutions found. The key conclusion in this paper is that GBEA’s can be used to create multiple good solutions needed to support engineering design.

  11. Treatment of Comorbid Attention-Deficit/Hyperactivity Disorder and Anxiety in Children : A Multiple Baseline Design Analysis

    ERIC Educational Resources Information Center

    Jarrett, Matthew A.; Ollendick, Thomas H.

    2012-01-01

    Objective: The present study evaluated a 10-week psychosocial treatment designed specifically for children with attention-deficit/hyperactivity disorder (ADHD) and a comorbid anxiety disorder. Method: Using a nonconcurrent multiple baseline design, the authors treated 8 children ages 8-12 with ADHD, combined type, and at least 1 of 3 major anxiety…

  12. Treatment of Comorbid Attention-Deficit/Hyperactivity Disorder and Anxiety in Children : A Multiple Baseline Design Analysis

    ERIC Educational Resources Information Center

    Jarrett, Matthew A.; Ollendick, Thomas H.

    2012-01-01

    Objective: The present study evaluated a 10-week psychosocial treatment designed specifically for children with attention-deficit/hyperactivity disorder (ADHD) and a comorbid anxiety disorder. Method: Using a nonconcurrent multiple baseline design, the authors treated 8 children ages 8-12 with ADHD, combined type, and at least 1 of 3 major anxiety…

  13. Theory vs. Bricks and Mortar--Forming, Norming, Storming, and Performing: The CEFPI Multiple Learning and Multiple Intelligence Design Charrette

    ERIC Educational Resources Information Center

    Robbie, Philip; Pickett, Fran

    2009-01-01

    A charrette (pronounced shuh-ret) is a collaborative planning process that harnesses the talents and energies of all interested parties to create a shared vision and a feasible plan for implementation. The charrette consists of an intense period of design activity where variables are clarified, reasonable limits established and collective…

  14. Theory vs. Bricks and Mortar--Forming, Norming, Storming, and Performing: The CEFPI Multiple Learning and Multiple Intelligence Design Charrette

    ERIC Educational Resources Information Center

    Robbie, Philip; Pickett, Fran

    2009-01-01

    A charrette (pronounced shuh-ret) is a collaborative planning process that harnesses the talents and energies of all interested parties to create a shared vision and a feasible plan for implementation. The charrette consists of an intense period of design activity where variables are clarified, reasonable limits established and collective…

  15. Barrier potential design criteria in multiple-quantum-well-based solar-cell structures

    NASA Technical Reports Server (NTRS)

    Mohaidat, Jihad M.; Shum, Kai; Wang, W. B.; Alfano, R. R.

    1994-01-01

    The barrier potential design criteria in multiple-quantum-well (MQW)-based solar-cell structures is reported for the purpose of achieving maximum efficiency. The time-dependent short-circuit current density at the collector side of various MQW solar-cell structures under resonant condition was numerically calculated using the time-dependent Schroedinger equation. The energy efficiency of solar cells based on the InAs/Ga(y)In(1-y)As and GaAs/Al(x)Ga(1-x)As MQW structues were compared when carriers are excited at a particular solar-energy band. Using InAs/Ga(y)In(1-y)As MQW structures it is found that a maximum energy efficiency can be achieved if the structure is designed with barrier potential of about 450 meV. The efficiency is found to decline linearly as the barrier potential increases for GaAs/Al(x)Ga(1-x)As MQW-structure-based solar cells.

  16. Barrier potential design criteria in multiple-quantum-well-based solar-cell structures

    NASA Technical Reports Server (NTRS)

    Mohaidat, Jihad M.; Shum, Kai; Wang, W. B.; Alfano, R. R.

    1994-01-01

    The barrier potential design criteria in multiple-quantum-well (MQW)-based solar-cell structures is reported for the purpose of achieving maximum efficiency. The time-dependent short-circuit current density at the collector side of various MQW solar-cell structures under resonant condition was numerically calculated using the time-dependent Schroedinger equation. The energy efficiency of solar cells based on the InAs/Ga(y)In(1-y)As and GaAs/Al(x)Ga(1-x)As MQW structues were compared when carriers are excited at a particular solar-energy band. Using InAs/Ga(y)In(1-y)As MQW structures it is found that a maximum energy efficiency can be achieved if the structure is designed with barrier potential of about 450 meV. The efficiency is found to decline linearly as the barrier potential increases for GaAs/Al(x)Ga(1-x)As MQW-structure-based solar cells.

  17. Stochastic production phase design for an open pit mining complex with multiple processing streams

    NASA Astrophysics Data System (ADS)

    Asad, Mohammad Waqar Ali; Dimitrakopoulos, Roussos; van Eldert, Jeroen

    2014-08-01

    In a mining complex, the mine is a source of supply of valuable material (ore) to a number of processes that convert the raw ore to a saleable product or a metal concentrate for production of the refined metal. In this context, expected variation in metal content throughout the extent of the orebody defines the inherent uncertainty in the supply of ore, which impacts the subsequent ore and metal production targets. Traditional optimization methods for designing production phases and ultimate pit limit of an open pit mine not only ignore the uncertainty in metal content, but, in addition, commonly assume that the mine delivers ore to a single processing facility. A stochastic network flow approach is proposed that jointly integrates uncertainty in supply of ore and multiple ore destinations into the development of production phase design and ultimate pit limit. An application at a copper mine demonstrates the intricacies of the new approach. The case study shows a 14% higher discounted cash flow when compared to the traditional approach.

  18. Two-Stage Path Planning Approach for Designing Multiple Spacecraft Reconfiguration Maneuvers

    NASA Technical Reports Server (NTRS)

    Aoude, Georges S.; How, Jonathan P.; Garcia, Ian M.

    2007-01-01

    The paper presents a two-stage approach for designing optimal reconfiguration maneuvers for multiple spacecraft. These maneuvers involve well-coordinated and highly-coupled motions of the entire fleet of spacecraft while satisfying an arbitrary number of constraints. This problem is particularly difficult because of the nonlinearity of the attitude dynamics, the non-convexity of some of the constraints, and the coupling between the positions and attitudes of all spacecraft. As a result, the trajectory design must be solved as a single 6N DOF problem instead of N separate 6 DOF problems. The first stage of the solution approach quickly provides a feasible initial solution by solving a simplified version without differential constraints using a bi-directional Rapidly-exploring Random Tree (RRT) planner. A transition algorithm then augments this guess with feasible dynamics that are propagated from the beginning to the end of the trajectory. The resulting output is a feasible initial guess to the complete optimal control problem that is discretized in the second stage using a Gauss pseudospectral method (GPM) and solved using an off-the-shelf nonlinear solver. This paper also places emphasis on the importance of the initialization step in pseudospectral methods in order to decrease their computation times and enable the solution of a more complex class of problems. Several examples are presented and discussed.

  19. Design of dual multiple aperture devices for dynamical fluence field modulated CT

    PubMed Central

    Mathews, Aswin John; Tilley, Steven; Gang, Grace; Kawamoto, Satomi; Zbijewski, Wojciech; Siewerdsen, Jeffrey H.; Levinson, Reuven; Webster Stayman, J.

    2016-01-01

    A Multiple Aperture Device (MAD) is a novel x-ray beam modulator that uses binary filtration on a fine scale to spatially modulate an x-ray beam. Using two MADs in series enables a large variety of fluence profiles by shifting the MADS relative to each other. This work details the design and control of dual MADs for a specific class of desired fluence patterns. Specifically, models of MAD operation are integrated into a best fit objective followed by CMA-ES optimization. To illustrate this framework we demonstrate the design process for an abdominal phantom with the goal of uniform detected signal. Achievable fluence profiles show good agreement with target fluence profiles, and the ability to flatten projections when a phantom is scanned is demonstrated. Simulated data reconstruction using traditional tube current modulation (TCM) and MAD filtering with TCM are investigated with the dual MAD system demonstrating more uniformity in noise and illustrating the potential for dose reduction under a maximum noise level constraint. PMID:28361128

  20. Impact of multiple matched controls on design sensitivity in observational studies.

    PubMed

    Rosenbaum, Paul R

    2013-03-01

    In an observational study, one treated subject may be matched for observed covariates to either one or several untreated controls. The common motivation for using several controls rather than one is to increase the power of a test of no effect under the doubtful assumption that matching for observed covariates suffices to remove bias from nonrandom treatment assignment. Does the choice between one or several matched controls affect the sensitivity of conclusions to violations of this doubtful assumption? With continuous responses, it is known that reducing the heterogeneity of matched pair differences reduces sensitivity to unmeasured biases, but increasing the sample size has a highly circumscribed effect on sensitivity to bias. Is the use of several controls rather than one analogous to a reduction in heterogeneity or to an increase in sample size? The issue is examined for Huber's m-statistics, including the t-test, the examination having three components: an example, asymptotic calculations using design sensitivity, and a simulation. Use of multiple controls with continuous responses yields a nontrivial reduction in sensitivity to unmeasured biases. An example looks at lead and cadmium in the blood of smokers from the 2008 National Health and Nutrition Examination Survey. A by-product of the discussion is a new result giving the design sensitivity for the permutation distribution of m-statistics.

  1. Attention training in socially anxious children: a multiple baseline design analysis.

    PubMed

    Cowart, Maria J W; Ollendick, Thomas H

    2011-10-01

    Current evidence has established an association between anxiety and attentional threat biases. Emerging research suggests these attentional biases may play a causal role in anxiety development. Clinical researchers have begun to develop treatments specifically designed to address these attentional processes. As such, Attention training (ATT) has been shown to be effective in the treatment of anxiety in adults. The current study represents an early attempt to implement ATT to treat social anxiety disorder (SOC) in children. Two boys meeting criteria for DSM-IV SOC participated in the study, along with their parents. Both boys received 10, 10-min sessions of ATT. A multiple-baseline design was used. Following treatment, both boys evidenced reductions in social anxiety. The current study provides preliminary evidence regarding the utility of ATT for treatment of childhood SOC. Future research is needed to further examine the use of this treatment strategy with youth and to explore the mechanisms of change. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Design and implementation of a low-cost multiple-range digital phase detector

    NASA Astrophysics Data System (ADS)

    Omran, Hesham; Albasha, Lutfi; Al-Ali, A. R.

    2012-06-01

    This article describes the design, simulation, implementation and testing of a novel low-cost multiple-range programmable digital phase detector. The detector receives two periodic signals and calculates the ratio of the time difference to the time period to measure and display the phase difference. The resulting output values are in integer form ranging from -180° to 180°. Users can select the detector pre-set operation frequency ranges using a three-bit pre-scalar. This enables to use the detector for various applications. The proposed detector can be programmed over a frequency range of 10 Hz to 25 kHz by configuring its clock divider circuit. Detector simulations were conducted and verified using ModelSim and the design was implemented and tested using an Altera Cyclone II field-programmable gate array board. Both the simulation and actual circuit testing results showed that the phase detector has a magnitude of error of only 1°. The detector is ideal for applications such as power factor measurement and correction, self-tuning resonant circuits and in metal detection systems. Unlike other stand-alone phase detection systems, the reported system has the ability to be programmed to several frequency ranges, hence expanding its bandwidth.

  3. On the Design, Development, and Analysis of Optimized Matrix-Vector Multiplication Routines for Coprocessors

    SciTech Connect

    Kabir, Khairul; Haidar, Azzam; Tomov, Stanimire; Dongarra, Jack J

    2015-01-01

    The manycore paradigm shift, and the resulting change in modern computer architectures, has made the development of optimal numerical routines extremely challenging. In this work, we target the development of numerical algorithms and implementations for Xeon Phi coprocessor architecture designs. In particular, we examine and optimize the general and symmetric matrix-vector multiplication routines (gemv/symv), which are some of the most heavily used linear algebra kernels in many important engineering and physics applications. We describe a successful approach on how to address the challenges for this problem, starting with our algorithm design, performance analysis and programing model and moving to kernel optimization. Our goal, by targeting low-level and easy to understand fundamental kernels, is to develop new optimization strategies that can be effective elsewhere for use on manycore coprocessors, and to show significant performance improvements compared to existing state-of-the-art implementations. Therefore, in addition to the new optimization strategies, analysis, and optimal performance results, we finally present the significance of using these routines/strategies to accelerate higher-level numerical algorithms for the eigenvalue problem (EVP) and the singular value decomposition (SVD) that by themselves are foundational for many important applications.

  4. Designing for multiple global user populations: increasing resource allocation efficiency for greater sustainability.

    PubMed

    Nadadur, G; Parkinson, M B

    2012-01-01

    This paper proposes a method to identify opportunities for increasing the efficiency of raw material allocation decisions for products that are simultaneously targeted at multiple user populations around the world. The values of 24 body measures at certain key percentiles were used to estimate the best-fitting anthropometric distributions for female and male adults in nine national populations, which were selected to represent the diverse target markets multinational companies must design for. These distributions were then used to synthesize body measure data for combined populations with a 1:1 female:male ratio. An anthropometric range metric (ARM) was proposed for assessing the variation of these body measures across the populations. At any percentile, ARM values were calculated as the percentage difference between the highest and lowest anthropometric values across the considered user populations. Based on their magnitudes, plots of ARM values computed between the 1st and 99 th percentiles for each body measure were grouped into low, medium, and high categories. This classification of body measures was proposed as a means of selecting the most suitable strategies for designing raw material-efficient products. The findings in this study and the contributions of subsequent work along these lines are expected to help achieve greater efficiencies in resource allocation in global product development.

  5. Designing an Electronic Patient Management System for Multiple Sclerosis: Building a Next Generation Multiple Sclerosis Documentation System

    PubMed Central

    Kern, Raimar; Haase, Rocco; Eisele, Judith Christina; Thomas, Katja

    2016-01-01

    Background Technologies like electronic health records or telemedicine devices support the rapid mediation of health information and clinical data independent of time and location between patients and their physicians as well as among health care professionals. Today, every part of the treatment process from diagnosis, treatment selection, and application to patient education and long-term care may be enhanced by a quality-assured implementation of health information technology (HIT) that also takes data security standards and concerns into account. In order to increase the level of effectively realized benefits of eHealth services, a user-driven needs assessment should ensure the inclusion of health care professional perspectives into the process of technology development as we did in the development process of the Multiple Sclerosis Documentation System 3D. After analyzing the use of information technology by patients suffering from multiple sclerosis, we focused on the needs of neurological health care professionals and their handling of health information technology. Objective Therefore, we researched the status quo of eHealth adoption in neurological practices and clinics as well as health care professional opinions about potential benefits and requirements of eHealth services in the field of multiple sclerosis. Methods We conducted a paper-and-pencil–based mail survey in 2013 by sending our questionnaire to 600 randomly chosen neurological practices in Germany. The questionnaire consisted of 24 items covering characteristics of participating neurological practices (4 items), the current use of network technology and the Internet in such neurological practices (5 items), physicians’ attitudes toward the general and MS-related usefulness of eHealth systems (8 items) and toward the clinical documentation via electronic health records (4 items), and physicians’ knowledge about the Multiple Sclerosis Documentation System (3 items). Results From 600 mailed

  6. Designing single- and multiple-shell sampling schemes for diffusion MRI using spherical code.

    PubMed

    Cheng, Jian; Shen, Dinggang; Yap, Pew-Thian

    2014-01-01

    In diffusion MRI (dMRI), determining an appropriate sampling scheme is crucial for acquiring the maximal amount of information for data reconstruction and analysis using the minimal amount of time. For single-shell acquisition, uniform sampling without directional preference is usually favored. To achieve this, a commonly used approach is the Electrostatic Energy Minimization (EEM) method introduced in dMRI by Jones et al. However, the electrostatic energy formulation in EEM is not directly related to the goal of optimal sampling-scheme design, i.e., achieving large angular separation between sampling points. A mathematically more natural approach is to consider the Spherical Code (SC) formulation, which aims to achieve uniform sampling by maximizing the minimal angular difference between sampling points on the unit sphere. Although SC is well studied in the mathematical literature, its current formulation is limited to a single shell and is not applicable to multiple shells. Moreover, SC, or more precisely continuous SC (CSC), currently can only be applied on the continuous unit sphere and hence cannot be used in situations where one or several subsets of sampling points need to be determined from an existing sampling scheme. In this case, discrete SC (DSC) is required. In this paper, we propose novel DSC and CSC methods for designing uniform single-/multi-shell sampling schemes. The DSC and CSC formulations are solved respectively by Mixed Integer Linear Programming (MILP) and a gradient descent approach. A fast greedy incremental solution is also provided for both DSC and CSC. To our knowledge, this is the first work to use SC formulation for designing sampling schemes in dMRI. Experimental results indicate that our methods obtain larger angular separation and better rotational invariance than the generalized EEM (gEEM) method currently used in the Human Connectome Project (HCP).

  7. Waveform Design and Diversity for Advanced Space-Time Adaptive Processing and Multiple Input Multiple Output Systems

    DTIC Science & Technology

    2012-08-01

    13. SUPPLEMENTARY NOTES 14. ABSTRACT Waveform diversity refers to the adaptivity of the radar waveform to dynamically optimize the... radar performance for the particular scenario and tasks. It may also exploit adaptivity in other domains, including the antenna radiation pattern (both...Specifically, in Chapter 1, we consider the problem of waveform design for radar sensors that operate in a noncooperative network. In Chapter 2, we deal

  8. Design of a multiple flyby mission to Phaethon, 2005UD and 1999YC

    NASA Astrophysics Data System (ADS)

    Sarli, Bruno; Arai, Tomoko; Kawakatsu, Yasuhiro

    3200 Phaethon is a B-type asteroid parent of the Geminid meteor shower and different from what is expected, Phaethon does not show any cometary features, unlike parent bodies (comets) for most of the meteor showers. The observed sodium depletion in the Geminid meteoroid suggests that Phaethon/Geminid can consist of primitive cometary materials and locally melted differentiated materials. The nature of Phaethon remains an open question and currently highly debated. Asteroids 2005UD and 1999YC are likely fragments originated from Phaethon due to their similar orbital properties, called PGC: Phaethon Geminid Complex. Also, a main-belt asteroid Pallas has been recently suggested to be genetically linked with Phaethon. Thus, making Phaethon a critical mission target to understand the chemical, physical and dynamic evolution of planetismals in the early solar system. A space mission to PGC can provide us with key information to understand the origins of Phaethon, PGC and possibly Pallas, and solve the fundamental issues in solar system sciences. Because of its scientific importance, Phaethon was a target candidate for NASA's Deep Impact mission and the OSIRIS-Rex mission. This study is developed assessing a multiple flyby mission for Phaethon, 2005UD and 1999YC. The objective is to design a simple multiple flyby mission based on ballistic transfers allied with gravity assisted maneuvers, identifying the global minimum energy trajectories taking into account the system design requirements, like an initial condition possible to be attained by the Epsilon rocket, Japan's latest launcher. Initial transfer results show periodical launch opportunities to all three asteroids with Phaethon been reached with less than 1 km/s. With a maximum of 3 km/s, several launch windows were obtained for Phaethon and 2005UD. However, 1999YC cannot be achieved with less than 4 km/s, unless a gravity assist maneuver is performed on Mars which allows an Earth-Mars-1999YC transfer with less than

  9. Modeling of Beams’ Multiple-Contact Mode with an Application in the Design of a High-g Threshold Microaccelerometer

    PubMed Central

    Li, Kai; Chen, Wenyuan; Zhang, Weiping

    2011-01-01

    Beam’s multiple-contact mode, characterized by multiple and discrete contact regions, non-uniform stoppers’ heights, irregular contact sequence, seesaw-like effect, indirect interaction between different stoppers, and complex coupling relationship between loads and deformation is studied. A novel analysis method and a novel high speed calculation model are developed for multiple-contact mode under mechanical load and electrostatic load, without limitations on stopper height and distribution, providing the beam has stepped or curved shape. Accurate values of deflection, contact load, contact region and so on are obtained directly, with a subsequent validation by CoventorWare. A new concept design of high-g threshold microaccelerometer based on multiple-contact mode is presented, featuring multiple acceleration thresholds of one sensitive component and consequently small sensor size. PMID:22163897

  10. Design and Imaging of Ground-Based Multiple-Input Multiple-Output Synthetic Aperture Radar (MIMO SAR) with Non-Collinear Arrays.

    PubMed

    Hu, Cheng; Wang, Jingyang; Tian, Weiming; Zeng, Tao; Wang, Rui

    2017-03-15

    Multiple-Input Multiple-Output (MIMO) radar provides much more flexibility than the traditional radar thanks to its ability to realize far more observation channels than the actual number of transmit and receive (T/R) elements. In designing the MIMO imaging radar arrays, the commonly used virtual array theory generally assumes that all elements are on the same line. However, due to the physical size of the antennas and coupling effect between T/R elements, a certain height difference between T/R arrays is essential, which will result in the defocusing of edge points of the scene. On the other hand, the virtual array theory implies far-field approximation. Therefore, with a MIMO array designed by this theory, there will exist inevitable high grating lobes in the imaging results of near-field edge points of the scene. To tackle these problems, this paper derives the relationship between target's point spread function (PSF) and pattern of T/R arrays, by which the design criterion is presented for near-field imaging MIMO arrays. Firstly, the proper height between T/R arrays is designed to focus the near-field edge points well. Secondly, the far-field array is modified to suppress the grating lobes in the near-field area. Finally, the validity of the proposed methods is verified by two simulations and an experiment.

  11. Design and Imaging of Ground-Based Multiple-Input Multiple-Output Synthetic Aperture Radar (MIMO SAR) with Non-Collinear Arrays

    PubMed Central

    Hu, Cheng; Wang, Jingyang; Tian, Weiming; Zeng, Tao; Wang, Rui

    2017-01-01

    Multiple-Input Multiple-Output (MIMO) radar provides much more flexibility than the traditional radar thanks to its ability to realize far more observation channels than the actual number of transmit and receive (T/R) elements. In designing the MIMO imaging radar arrays, the commonly used virtual array theory generally assumes that all elements are on the same line. However, due to the physical size of the antennas and coupling effect between T/R elements, a certain height difference between T/R arrays is essential, which will result in the defocusing of edge points of the scene. On the other hand, the virtual array theory implies far-field approximation. Therefore, with a MIMO array designed by this theory, there will exist inevitable high grating lobes in the imaging results of near-field edge points of the scene. To tackle these problems, this paper derives the relationship between target’s point spread function (PSF) and pattern of T/R arrays, by which the design criterion is presented for near-field imaging MIMO arrays. Firstly, the proper height between T/R arrays is designed to focus the near-field edge points well. Secondly, the far-field array is modified to suppress the grating lobes in the near-field area. Finally, the validity of the proposed methods is verified by two simulations and an experiment. PMID:28294996

  12. SpaRibs Geometry Parameterization for Wings with Multiple Sections using Single Design

    NASA Technical Reports Server (NTRS)

    De, Shuvodeep; Jrad, Mohamed; Locatelli, Davide; Kapania, Rakesh K.; Baker, Myles; Pak, Chan-Gi

    2017-01-01

    The SpaRibs topology of an aircraft wing has a significant effect on its structural behavior and stability as well as the flutter performance. The development of additive manufacturing techniques like Electron Beam Free Form Fabrication (EBF3) has made it feasible to manufacture aircraft wings with curvilinear spars, ribs (SpaRibs) and stiffeners. In this article a new global-local optimization framework for wing with multiple sections using curvilinear SpaRibs is described. A single design space is used to parameterize the SpaRibs geometry. This method has been implemented using MSC-PATRAN to create a broad range of SpaRibs topologies using limited number of parameters. It ensures C0 and C1 continuities in SpaRibs geometry at the junction of two wing sections with airfoil thickness gradient discontinuity as well as mesh continuity between all structural components. This method is advantageous in complex multi-disciplinary optimization due to its potential to reduce the number of design variables. For the global-local optimization the local panels are generated by an algorithm which is totally based on a set algebra on the connectivity matrix data. The great advantage of this method is that it is completely independent of the coordinates of the nodes of the finite element model. It is also independent of the order in which the elements are distributed in the FEM. The code is verified by optimizing of the CRM Baseline model at trim condition at Mach number equal to 0.85 for five different angle of attack (-2deg, 0deg,2deg,4deg and 6deg). The final weight of the wing is 19,090.61 lb. This value is comparable to that obtained by Qiang et al. 6 (19,269 lb).

  13. Space station definitions, design, and development. Task 5: Multiple arm telerobot coordination and control: Manipulator design methodology

    NASA Technical Reports Server (NTRS)

    Stoughton, R. M.

    1990-01-01

    A proposed methodology applicable to the design of manipulator systems is described. The current design process is especially weak in the preliminary design phase, since there is no accepted measure to be used in trading off different options available for the various subsystems. The design process described uses Cartesian End-Effector Impedance as a measure of performance for the system. Having this measure of performance, it is shown how it may be used to determine the trade-offs necessary to the preliminary design phase. The design process involves three main parts: (1) determination of desired system performance in terms of End-Effector Impedance; (2) trade-off design options to achieve this desired performance; and (3) verification of system performance through laboratory testing. The design process is developed using numerous examples and experiments to demonstrate the feasability of this approach to manipulator design.

  14. Design and implementation of a contactless multiple hand feature acquisition system

    NASA Astrophysics Data System (ADS)

    Zhao, Qiushi; Bu, Wei; Wu, Xiangqian; Zhang, David

    2012-06-01

    In this work, an integrated contactless multiple hand feature acquisition system is designed. The system can capture palmprint, palm vein, and palm dorsal vein images simultaneously. Moreover, the images are captured in a contactless manner, that is, users need not to touch any part of the device when capturing. Palmprint is imaged under visible illumination while palm vein and palm dorsal vein are imaged under near infrared (NIR) illumination. The capturing is controlled by computer and the whole process is less than 1 second, which is sufficient for online biometric systems. Based on this device, this paper also implements a contactless hand-based multimodal biometric system. Palmprint, palm vein, palm dorsal vein, finger vein, and hand geometry features are extracted from the captured images. After similarity measure, the matching scores are fused using weighted sum fusion rule. Experimental results show that although the verification accuracy of each uni-modality is not as high as that of state-of-the-art, the fusion result is superior to most of the existing hand-based biometric systems. This result indicates that the proposed device is competent in the application of contactless multimodal hand-based biometrics.

  15. Designing for Online Collaborations and Local Environmental Action In Citizen Science: A Multiple Case Study

    NASA Astrophysics Data System (ADS)

    Kermish-Allen, Ruth

    Traditional citizen science projects have been based on the scientific communities need to gather vast quantities of high quality data, neglecting to ask what the project participants get in return. How can participants be seen more as collaborative partners in citizen science projects? Online communities for citizen science are expanding rapidly, giving participants the opportunity to take part in a wide range of activities, from monitoring invasive species to identifying far-off galaxies. These communities can bring together the virtual and physical worlds in new ways that are egalitarian, collaborative, applied, localized and globalized to solve real environmental problems. There are a small number of citizen science projects that leverage the affordances of an online community to connect, engage, and empower participants to make local change happen. This multiple case study applies a conceptual framework rooted in sociocultural learning theory, Non-Hierarchical Online Learning Communities (NHOLCs), to three online citizen communities that have successfully fostered online collaboration and on-the-ground environmental actions. The purpose of the study is to identify the range and variation of the online and programmatic functions available in each project. The findings lead to recommendations for designing these innovative communities, specifically the technological and programmatic components of online citizen science communities that support environmental actions in our backyards.

  16. Design and Control of an Embedded Vision Guided Robotic Fish with Multiple Control Surfaces

    PubMed Central

    Wang, Kai; Tan, Min; Zhang, Jianwei

    2014-01-01

    This paper focuses on the development and control issues of a self-propelled robotic fish with multiple artificial control surfaces and an embedded vision system. By virtue of the hybrid propulsion capability in the body plus the caudal fin and the complementary maneuverability in accessory fins, a synthesized propulsion scheme including a caudal fin, a pair of pectoral fins, and a pelvic fin is proposed. To achieve flexible yet stable motions in aquatic environments, a central pattern generator- (CPG-) based control method is employed. Meanwhile, a monocular underwater vision serves as sensory feedback that modifies the control parameters. The integration of the CPG-based motion control and the visual processing in an embedded microcontroller allows the robotic fish to navigate online. Aquatic tests demonstrate the efficacy of the proposed mechatronic design and swimming control methods. Particularly, a pelvic fin actuated sideward swimming gait was first implemented. It is also found that the speeds and maneuverability of the robotic fish with coordinated control surfaces were largely superior to that of the swimming robot propelled by a single control surface. PMID:24688413

  17. A multiple chamber, semicontinuous, crop carbon dioxide exchange system: design, calibration, and data interpretation

    NASA Technical Reports Server (NTRS)

    van Iersel, M. W.; Bugbee, B.

    2000-01-01

    Long-term, whole crop CO2 exchange measurements can be used to study factors affecting crop growth. These factors include daily carbon gain, cumulative carbon gain, and carbon use efficiency, which cannot be determined from short-term measurements. We describe a system that measures semicontinuously crop CO2 exchange in 10 chambers over a period of weeks or months. Exchange of CO2 in every chamber can be measured at 5 min intervals. The system was designed to be placed inside a growth chamber, with additional environmental control provided by the individual gas exchange chambers. The system was calibrated by generating CO2 from NaHCO3 inside the chambers, which indicated that accuracy of the measurements was good (102% and 98% recovery for two separate photosynthesis systems). Since the systems measure net photosynthesis (P-net, positive) and dark respiration(R-dark, negative), the data can be used to estimate gross photosynthesis, daily carbon gain, cumulative carbon gain, and carbon use efficiency. Continuous whole-crop measurements are a valuable tool that complements leaf photosynthesis measurements. Multiple chambers allow for replication and comparison among several environmental or cultural treatments that may affect crop growth. Example data from a 2 week study with petunia (Petunia x hybrida Hort. Vilm.-Andr.) are presented to illustrate some of the capabilities of this system.

  18. Design and control of an embedded vision guided robotic fish with multiple control surfaces.

    PubMed

    Yu, Junzhi; Wang, Kai; Tan, Min; Zhang, Jianwei

    2014-01-01

    This paper focuses on the development and control issues of a self-propelled robotic fish with multiple artificial control surfaces and an embedded vision system. By virtue of the hybrid propulsion capability in the body plus the caudal fin and the complementary maneuverability in accessory fins, a synthesized propulsion scheme including a caudal fin, a pair of pectoral fins, and a pelvic fin is proposed. To achieve flexible yet stable motions in aquatic environments, a central pattern generator- (CPG-) based control method is employed. Meanwhile, a monocular underwater vision serves as sensory feedback that modifies the control parameters. The integration of the CPG-based motion control and the visual processing in an embedded microcontroller allows the robotic fish to navigate online. Aquatic tests demonstrate the efficacy of the proposed mechatronic design and swimming control methods. Particularly, a pelvic fin actuated sideward swimming gait was first implemented. It is also found that the speeds and maneuverability of the robotic fish with coordinated control surfaces were largely superior to that of the swimming robot propelled by a single control surface.

  19. Multiple factor design for reactive mixture selection for use in reactive walls in mine drainage treatment.

    PubMed

    Cocos, Ioana A; Zagury, Gerald J; Clément, Bernard; Samson, Réjean

    2002-01-01

    Sulfate-reducing reactive walls installed in situ in the path of acid mine drainage contaminated groundwater, present a promising passive treatment technology. However, a rigorous and methodical selection of the most appropriate reactive mixture composition still needs to be investigated. The aim of this study was the selection of the most reactive medium using a multiple factor design and the modeling of the sulfate-reduction rate. Reactivity of 17 mixtures was assessed in batch reactors (in duplicates) using a synthetic AMD. Results indicate that within 41 days, sulfate concentrations decreased from initial concentrations of 2,000-3,200 mg/l to final concentrations of <90 mg/l. Metal removal efficiencies ranged between 51-84% for Ni and 73-93% for Zn. Generated sulfate-reduction rate predictive models which had very satisfactory parameters (R2 = 0.86, F = 62.38 (p-level < 10(-13)) and R2 = 0.90. F = 62.30 (p-level < 10(-13))) identified poultry manure and two other carbon sources as the critical variables for sulfate-reduction rate.

  20. Design of an image encryption scheme based on a multiple chaotic map

    NASA Astrophysics Data System (ADS)

    Tong, Xiao-Jun

    2013-07-01

    In order to solve the problem that chaos is degenerated in limited computer precision and Cat map is the small key space, this paper presents a chaotic map based on topological conjugacy and the chaotic characteristics are proved by Devaney definition. In order to produce a large key space, a Cat map named block Cat map is also designed for permutation process based on multiple-dimensional chaotic maps. The image encryption algorithm is based on permutation-substitution, and each key is controlled by different chaotic maps. The entropy analysis, differential analysis, weak-keys analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new image encryption scheme. Through the comparison to the proposed scheme with AES, DES and Logistic encryption methods, we come to the conclusion that the image encryption method solves the problem of low precision of one dimensional chaotic function and has higher speed and higher security.

  1. Precoder design for indoor visible light communications with multiple RGB LEDs

    NASA Astrophysics Data System (ADS)

    Gao, Qian; Lang, Tian; Bo, Feng; Chen, Gang; Hua, Yingbo

    2013-09-01

    In this paper, we consider the problem of precoder design for an optical intensity modulation (IM) system with multiple redgreen- blue (RGB) light emitting diodes (LEDs) as transmitters and imaging lens with color filters as receivers. The purpose of using a precoder is to optimally allocate power for each LED based on the current channel condition to minimize the detection error rate. To achieve the goal, an non-convex optimization problem due to a nonconvex constraint is formulated first taking into account several crucial lighting constraints, such as flicker-free, color rendering index (CRI), and luminous efficacy rate (LER) as well as the average optical intensity constraint and non-negative transmitter-side signal constraint. By manipulations we transform the problem into a semi-definite programming (SDP) and by approximation we relaxed the non-convex constraint into a convex one. The resulting convex problem is iteratively solved by CVX, an add-in to MATLAB, which jointly optimizes the precoder and DC-biases driving each LED. We assume that M-PAM signal constellation is used as input to the precoder and an MMSE receiver is applied to recover the input signals in this paper, while our method is not restrict to the specific choice.

  2. Multicomponent cognitive-behavioural intervention to improve sleep in adolescents: a multiple baseline design.

    PubMed

    Hendricks, Melissa C; Ward, Cynthia M; Grodin, Lauren K; Slifer, Keith J

    2014-05-01

    Adolescents are prone to sleep problems that have unique developmental aspects and contribute to physical, emotional, and behavioural problems. This study evaluated an individualized, multicomponent intervention that considered developmental factors, and promoted age-appropriate autonomy in three adolescent females with disrupted sleep. Adolescents recorded sleep data on daily logs. A nonconcurrent multiple baseline design was used to evaluate a cognitive-behavioural intervention including sleep hygiene training, bedtime routine development, cognitive restructuring, relaxation training, stimulus control, sleep restriction, bedtime fading, and problem-solving, along with clinically indicated individualization. Outcomes demonstrated clinically meaningful improvements and decreased variability in sleep parameters following intervention. Each participant's sleep log data indicated improvement in, or maintenance of, adequate total sleep time (TST), decreased sleep onset latency (SOL), improved sleep efficiency (SE), improvement in time of sleep onset, and decreased or continued low frequency of night awakenings (NA). Anecdotally, adolescents and parents reported improvement in daytime functioning, coping, and sense of wellbeing. These cases highlight the potential for cognitive-behavioural interventions to facilitate healthy sleep in adolescents with challenging sleep problems.

  3. Intercessory prayer in psychological well-being: using a multiple-baseline, across-subjects design.

    PubMed

    Tloczynski, Joseph; Fritzsch, Sonja

    2002-12-01

    Undergraduates from an upper-level psychology course were volunteer participants in the study. The 8 participants were to be prayed for in a Multiple Baseline Across Subjects research design, which included a 1-week minimum baseline period for all subjects followed by the sequential presentation of the independent variable so that every two weeks, two additional subjects were being prayed for until all but 2 participants, who maintained baseline, were exposed to being prayed for at 7 weeks. All participants were prayed for by one of the experimenters using a nondirective method of prayer where no specific requests were made. All subjects completed the Taylor Manifest Anxiety Scale on a daily basis for 5 weeks and the Minnesota Multiphasic Personality Inventory-2 on a weekly basis for 7 weeks. Analysis of data identified significant reductions in anxiety scores on both the tests for subjects who were prayed for but not for those who were not prayed for. Subjects' lower mean anxiety scores somewhat matched the sequential timing of being prayed for.

  4. Comparison of randomization-test procedures for single-case multiple-baseline designs.

    PubMed

    Levin, Joel R; Ferron, John M; Gafurov, Boris S

    2016-07-01

    In three simulation investigations, we examined the statistical properties of several different randomization-test procedures for analyzing the data from single-case multiple-baseline intervention studies. Two procedures (Wampold-Worsham and Revusky) are associated with single fixed intervention start points and three are associated with randomly determined intervention start points. Of the latter three, one (Koehler-Levin) is an existing procedure that has been previously examined and the other two (modified Revusky and restricted Marascuilo-Busk) are modifications and extensions of existing procedures. All five procedures were found to maintain their Type I error probabilities at acceptable levels. In most of the conditions investigated here, two of the random start-point procedures (Koehler-Levin and restricted Marascuilo-Busk) were more powerful than the others with respect to detecting immediate abrupt intervention effects. For designs in which it is not possible to include the same series lengths for all cases, either the modified Revusky or restricted Marascuilo-Busk procedure is recommended.

  5. Imagery Rescripting for Body Dysmorphic Disorder: A Multiple-Baseline Single-Case Experimental Design.

    PubMed

    Willson, Rob; Veale, David; Freeston, Mark

    2016-03-01

    Individuals with body dysmorphic disorder (BDD) often experience negative distorted images of their appearance, and research suggests these may be linked to memories of adverse events such as bullying or teasing. This study evaluates imagery rescripting (ImR) as an intervention for BDD. In this article, we present a multiple-baseline single-case experimental design testing imagery rescripting as a brief, stand-alone intervention, with six individuals with BDD that related to aversive memories. The impact of the intervention was assessed by self-reported daily measures of symptom severity (preoccupation with appearance, appearance-related checking behaviors, appearance-related distress, and strength of belief that their main problem is their appearance) and standardized clinician ratings of BDD severity (Yale-Brown Obsessive Compulsive Scale modified for BDD). Four out of six of the participants responded positively to the intervention, with clinically meaningful improvement in symptomatology. Overall response was rapid; improvements began within the first week post-ImR intervention. From a small sample it is cautiously concluded that imagery rescripting may show promise as a module in cognitive-behavioral therapy for BDD, and is worthy of further investigation. Copyright © 2015. Published by Elsevier Ltd.

  6. Studies With Staggered Starts: Multiple Baseline Designs and Group-Randomized Trials

    PubMed Central

    Murray, David M.; Andridge, Rebecca R.; Pennell, Michael L.; Hade, Erinn M.

    2011-01-01

    Objectives. Multiple baseline designs (MBDs) have been suggested as alternatives to group-randomized trials (GRT). We reviewed structural features of MBDs and considered their potential effectiveness in public health research. We also reviewed the effect of staggered starts on statistical power. Methods. We reviewed the MBD literature to identify key structural features, recent suggestions that MBDs be adopted in public health research, and the literature on power in GRTs with staggered starts. We also computed power for MBDs and GRTs. Results. The features that have contributed to the success of small MBDs in some fields are not likely to translate well to public health research. MBDs can be more powerful than GRTs under some conditions, but those conditions involve assumptions that require careful evaluation in practice. Conclusions. MBDs will often serve better as a complement of rather than as an alternative to GRTs. GRTs may employ staggered starts for logistical or ethical reasons, but this will always increase their duration and will often increase their cost. PMID:21940928

  7. A multiple chamber, semicontinuous, crop carbon dioxide exchange system: design, calibration, and data interpretation

    NASA Technical Reports Server (NTRS)

    van Iersel, M. W.; Bugbee, B.

    2000-01-01

    Long-term, whole crop CO2 exchange measurements can be used to study factors affecting crop growth. These factors include daily carbon gain, cumulative carbon gain, and carbon use efficiency, which cannot be determined from short-term measurements. We describe a system that measures semicontinuously crop CO2 exchange in 10 chambers over a period of weeks or months. Exchange of CO2 in every chamber can be measured at 5 min intervals. The system was designed to be placed inside a growth chamber, with additional environmental control provided by the individual gas exchange chambers. The system was calibrated by generating CO2 from NaHCO3 inside the chambers, which indicated that accuracy of the measurements was good (102% and 98% recovery for two separate photosynthesis systems). Since the systems measure net photosynthesis (P-net, positive) and dark respiration(R-dark, negative), the data can be used to estimate gross photosynthesis, daily carbon gain, cumulative carbon gain, and carbon use efficiency. Continuous whole-crop measurements are a valuable tool that complements leaf photosynthesis measurements. Multiple chambers allow for replication and comparison among several environmental or cultural treatments that may affect crop growth. Example data from a 2 week study with petunia (Petunia x hybrida Hort. Vilm.-Andr.) are presented to illustrate some of the capabilities of this system.

  8. Control and design of multiple unmanned air vehicles for persistent surveillance

    NASA Astrophysics Data System (ADS)

    Nigam, Nikhil

    Control of multiple autonomous aircraft for search and exploration, is a topic of current research interest for applications such as weather monitoring, geographical surveys, search and rescue, tactical reconnaissance, and extra-terrestrial exploration, and the need to distribute sensing is driven by considerations of efficiency, reliability, cost and scalability. Hence, this problem has been extensively studied in the fields of controls and artificial intelligence. The task of persistent surveillance is different from a coverage/exploration problem, in that all areas need to be continuously searched, minimizing the time between visitations to each region in the target space. This distinction does not allow a straightforward application of most exploration techniques to the problem, although ideas from these methods can still be used. The use of aerial vehicles is motivated by their ability to cover larger spaces and their relative insensitivity to terrain. However, the dynamics of Unmanned Air Vehicles (UAVs) adds complexity to the control problem. Most of the work in the literature decouples the vehicle dynamics and control policies, but their interaction is particularly interesting for a surveillance mission. Stochastic environments and UAV failures further enrich the problem by requiring the control policies to be robust, and this aspect is particularly important for hardware implementations. For a persistent mission, it becomes imperative to consider the range/endurance constraints of the vehicles. The coupling of the control policy with the endurance constraints of the vehicles is an aspect that has not been sufficiently explored. Design of UAVs for desirable mission performance is also an issue of considerable significance. The use of a single monolithic optimization for such a problem has practical limitations, and decomposition-based design is a potential alternative. In this research high-level control policies are devised, that are scalable, reliable

  9. Design-Build-Write: Increasing the Impact of English for Specific Purposes Learning and Teaching in Aeronautical Engineering Education through Multiple Intelligences Task Design

    ERIC Educational Resources Information Center

    Tatzl, Dietmar

    2011-01-01

    This article presents an English for Specific Purposes (ESP) task developed for teaching aeronautical engineering students. The task Design-Build-Write rests on the assumption that engineering students are skilled at mathematical reasoning, problem solving, drawing and constructing. In Gardner's 1983 Multiple Intelligences (MI) theory, these…

  10. An Examination of the Decision-Making Process Used by Designers in Multiple Disciplines

    ERIC Educational Resources Information Center

    Stefaniak, Jill E.; Tracey, Monica W.

    2014-01-01

    Design-thinking is an inductive and participatory process in which designers are required to manage constraints, generate solutions, and follow project timelines in order to complete project goals. The researchers used this exploration study to look at how designers in various disciplinary fields approach design projects. Designers were asked to…

  11. An Examination of the Decision-Making Process Used by Designers in Multiple Disciplines

    ERIC Educational Resources Information Center

    Stefaniak, Jill E.; Tracey, Monica W.

    2014-01-01

    Design-thinking is an inductive and participatory process in which designers are required to manage constraints, generate solutions, and follow project timelines in order to complete project goals. The researchers used this exploration study to look at how designers in various disciplinary fields approach design projects. Designers were asked to…

  12. A landscape lake flow pattern design approach based on automated CFD simulation and parallel multiple objective optimization.

    PubMed

    Guo, Hao; Tian, Yimei; Shen, Hailiang; Wang, Yi; Kang, Mengxin

    A design approach for determining the optimal flow pattern in a landscape lake is proposed based on FLUENT simulation, multiple objective optimization, and parallel computing. This paper formulates the design into a multi-objective optimization problem, with lake circulation effects and operation cost as two objectives, and solves the optimization problem with non-dominated sorting genetic algorithm II. The lake flow pattern is modelled in FLUENT. The parallelization aims at multiple FLUENT instance runs, which is different from the FLUENT internal parallel solver. This approach: (1) proposes lake flow pattern metrics, i.e. weighted average water flow velocity, water volume percentage of low flow velocity, and variance of flow velocity, (2) defines user defined functions for boundary setting, objective and constraints calculation, and (3) parallels the execution of multiple FLUENT instances runs to significantly reduce the optimization wall-clock time. The proposed approach is demonstrated through a case study for Meijiang Lake in Tianjin, China.

  13. Practicing School Consultants Can Empirically Validate Interventions: A Description and Demonstration of the Non-Concurrent Multiple-Baseline Design

    ERIC Educational Resources Information Center

    Winn, Beth D.; Skinner, Christopher H.; Allin, Jessica D.; Hawkins, James A.

    2004-01-01

    The purpose of this manuscript is to describe and demonstrate how practicing school psychologists who are serving as consultants can empirically validate interventions using the non-concurrent multiple-baseline across-subjects (Non-Con M-B A-S) design. Over the course of a school year, three teachers, from different elementary schools, each…

  14. The Validity of a Multiple-Choice, Paper and Pencil Instrument in Discriminating between Masters and Nonmasters of Instructional Design.

    ERIC Educational Resources Information Center

    Stepp, Sidney Leland; Shrock, Sharon A.

    While surveys have identified instructional design competencies, there has been virtually no systematic research of alternative means for assessing professional competence in this area. This paper reports on a study which investigated the question of whether a multiple-choice, paper and pencil test can validly discriminate between levels of…

  15. Practicing School Consultants Can Empirically Validate Interventions: A Description and Demonstration of the Non-Concurrent Multiple-Baseline Design

    ERIC Educational Resources Information Center

    Winn, Beth D.; Skinner, Christopher H.; Allin, Jessica D.; Hawkins, James A.

    2004-01-01

    The purpose of this manuscript is to describe and demonstrate how practicing school psychologists who are serving as consultants can empirically validate interventions using the non-concurrent multiple-baseline across-subjects (Non-Con M-B A-S) design. Over the course of a school year, three teachers, from different elementary schools, each…

  16. CARRS Surveillance study: design and methods to assess burdens from multiple perspectives

    PubMed Central

    2012-01-01

    Background Cardio-metabolic diseases (CMDs) are a growing public health problem, but data on incidence, trends, and costs in developing countries is scarce. Comprehensive and standardised surveillance for non-communicable diseases was recommended at the United Nations High-level meeting in 2011. Aims: To develop a model surveillance system for CMDs and risk factors that could be adopted for continued assessment of burdens from multiple perspectives in South-Asian countries. Methods Design: Hybrid model with two cross-sectional serial surveys three years apart to monitor trend, with a three-year prospective follow-up of the first cohort. Sites: Three urban settings (Chennai and New Delhi in India; Karachi in Pakistan), 4000 participants in each site stratified by gender and age. Sampling methodology: Multi-stage cluster random sampling; followed by within-household participant selection through a combination of Health Information National Trends Study (HINTS) and Kish methods. Culturally-appropriate and methodologically-relevant data collection instruments were developed to gather information on CMDs and their risk factors; quality of life, health-care utilisation and costs, along with objective measures of anthropometric, clinical and biochemical parameters. The cohort follow-up is designed as a pilot study to understand the feasibility of estimating incidence of risk factors, disease events, morbidity, and mortality. Results The overall participant response rate in the first cross-sectional survey was 94.1% (Chennai 92.4%, n = 4943; Delhi 95.7%, n = 4425; Karachi 94.3%, n = 4016). 51.8% of the participants were females, 61.6% < 45years, 27.5% 45–60years and 10.9% >60 years. Discussion This surveillance model will generate data on prevalence and trends; help study the complex life-course patterns of CMDs, and provide a platform for developing and testing interventions and tools for prevention and control of CMDs in South-Asia. It will also help

  17. The integration of occupational therapy into primary care: a multiple case study design

    PubMed Central

    2013-01-01

    Background For over two decades occupational therapists have been encouraged to enhance their roles within primary care and focus on health promotion and prevention activities. While there is a clear fit between occupational therapy and primary care, there have been few practice examples, despite a growing body of evidence to support the role. In 2010, the province of Ontario, Canada provided funding to include occupational therapists as members of Family Health Teams, an interprofessional model of primary care. The integration of occupational therapists into this model of primary care is one of the first large scale initiatives of its kind in North America. The objective of the study was to examine how occupational therapy services are being integrated into primary care teams and understand the structures supporting the integration. Methods A multiple case study design was used to provide an in-depth description of the integration of occupational therapy. Four Family Health Teams with occupational therapists as part of the team were identified. Data collection included in-depth interviews, document analyses, and questionnaires. Results Each Family Health Team had a unique organizational structure that contributed to the integration of occupational therapy. Communication, trust and understanding of occupational therapy were key elements in the integration of occupational therapy into Family Health Teams, and were supported by a number of strategies including co-location, electronic medical records and team meetings. An understanding of occupational therapy was critical for integration into the team and physicians were less likely to understand the occupational therapy role than other health providers. Conclusion With an increased emphasis on interprofessional primary care, new professions will be integrated into primary healthcare teams. The study found that explicit strategies and structures are required to facilitate the integration of a new professional group

  18. Transitioning from Additive to Multiplicative Thinking: A Design and Teaching Experiment with Third through Fifth Graders

    ERIC Educational Resources Information Center

    Brickwedde, James

    2011-01-01

    The maturation of multiplicative thinking is key to student progress in middle school as rational number, ratio, and proportion concepts are encountered. But many students arrive from the intermediate grades and falter in developing this essential disposition. Elementary students have historically learned multiplication and division as operation…

  19. Design and Delivery of Multiple Server-Side Computer Languages Course

    ERIC Educational Resources Information Center

    Wang, Shouhong; Wang, Hai

    2011-01-01

    Given the emergence of service-oriented architecture, IS students need to be knowledgeable of multiple server-side computer programming languages to be able to meet the needs of the job market. This paper outlines the pedagogy of an innovative course of multiple server-side computer languages for the undergraduate IS majors. The paper discusses…

  20. Design and Delivery of Multiple Server-Side Computer Languages Course

    ERIC Educational Resources Information Center

    Wang, Shouhong; Wang, Hai

    2011-01-01

    Given the emergence of service-oriented architecture, IS students need to be knowledgeable of multiple server-side computer programming languages to be able to meet the needs of the job market. This paper outlines the pedagogy of an innovative course of multiple server-side computer languages for the undergraduate IS majors. The paper discusses…

  1. Learning Physics Teaching through Collaborative Design of Conceptual Multiple-Choice Questions

    ERIC Educational Resources Information Center

    Milner-Bolotin, Marina

    2015-01-01

    Increasing student engagement through Electronic Response Systems (clickers) has been widely researched. Its success largely depends on the quality of multiple-choice questions used by instructors. This paper describes a pilot project that focused on the implementation of online collaborative multiple-choice question repository, PeerWise, in a…

  2. Design space construction of multiple dose-strength tablets utilizing bayesian estimation based on one set of design-of-experiments.

    PubMed

    Maeda, Jin; Suzuki, Tatsuya; Takayama, Kozo

    2012-01-01

    Design spaces for multiple dose strengths of tablets were constructed using a Bayesian estimation method with one set of design of experiments (DoE) of only the highest dose-strength tablet. The lubricant blending process for theophylline tablets with dose strengths of 100, 50, and 25 mg is used as a model manufacturing process in order to construct design spaces. The DoE was conducted using various Froude numbers (X(1)) and blending times (X(2)) for theophylline 100-mg tablet. The response surfaces, design space, and their reliability of the compression rate of the powder mixture (Y(1)), tablet hardness (Y(2)), and dissolution rate (Y(3)) of the 100-mg tablet were calculated using multivariate spline interpolation, a bootstrap resampling technique, and self-organizing map clustering. Three experiments under an optimal condition and two experiments under other conditions were performed using 50- and 25-mg tablets, respectively. The response surfaces of the highest-strength tablet were corrected to those of the lower-strength tablets by Bayesian estimation using the manufacturing data of the lower-strength tablets. Experiments under three additional sets of conditions of lower-strength tablets showed that the corrected design space made it possible to predict the quality of lower-strength tablets more precisely than the design space of the highest-strength tablet. This approach is useful for constructing design spaces of tablets with multiple strengths.

  3. Time-of-flight diffractometer with multiple pulse overlap - an example for the application of modern tools for instrument design

    SciTech Connect

    Stuhr, U.; Bauer, G.S.; Wagner, W.

    1997-09-01

    A Time-of-Flight Diffractometer with high pulse rates, allowing multiple frame overlap, is a completely novel design of an instrument dedicated for high resolution strain-field mapping. We elaborated a detailed concept of this instrument applying analytical calculations and Monte Carlo computer simulations. Having established the instrument concept, the computer simulations will now be extended to optimize the total performance of the instrument. To illustrate the necessity and possibilities of applying modem tools for instrument design, we describe, as an example, the different steps towards the development of the detailed design of this instrument, which we intend to build at the Swiss spallation. source SINQ in the near future.

  4. SWiss Atorvastatin and interferon Beta-1b trial In Multiple Sclerosis (SWABIMS)--rationale, design and methodology.

    PubMed

    Kamm, Christian P; Mattle, Heinrich P

    2009-12-14

    Statins have anti-inflammatory and immunomodulatory properties in addition to their lipid-lowering effects. Currently, the effects of statins on multiple sclerosis are still controversial. Therefore, randomized clinical trials are needed to provide better evidence on the therapeutic potential of statins in multiple sclerosis. The SWiss Atorvastatin and Interferon Beta-1b trial in Multiple Sclerosis (SWABIMS) evaluates the efficacy, safety and tolerability of atorvastatin 40 mg per os daily and subcutaneous interferon beta-1b every other day compared to monotherapy with subcutaneous interferon beta-1b every other day in patients with relapsing-remitting multiple sclerosis. SWABIMS is a multi-centre, randomized, parallel-group, rater-blinded, Phase IIb-study conducted in eight hospitals in Switzerland. 80 treatment naïve patients with relapsing-remitting forms of multiple sclerosis will receive subcutaneous interferon beta-1b for three months. Afterwards, they are randomized into two equal-sized parallel arms, receiving atorvastatin 40 mg/d or not in addition to interferon beta-1b for another 12 months. Disease activity measured by the proportion of patients with new T2 lesions is the primary endpoint. SWABIMS is designed to give further information about the therapeutic effect of atorvastatin 40 mg per os daily as add-on therapy to interferon beta-1b in patients with relapsing-remitting multiple sclerosis. Furthermore important safety and tolerability data will be generated. http://www.clinicaltrials.gov. Identifier: NCT00942591; Swissmedic reference number: 2005DR2119.

  5. Mission Design for a Multiple-Rendezvous Mission to Jupiter's Trojans

    NASA Astrophysics Data System (ADS)

    Maiwald, Volker; Dachwald, Bernd

    In this paper, we will provide a feasible mission design for a multiple-rendezvous mission to Jupiter's Trojans. It is based on solar electric propulsion, as being currently used on the DAWN spacecraft, and other flight-proven technology. First, we have selected a set of mission objectives, the prime objective being the detection of water -especially subsurface water -to provide evidence for the Trojans' formation at large solar distances. Based on DAWN and other comparable missions, we have determined suitable payload instruments to achieve these objectives. Afterwards, we have designed a spacecraft that is able to carry the selected payload to the Trojan region and rendezvous successively with three target bodies within a maximum mission duration of 15 years. Accurate low-thrust trajectories have been obtained with a global low-thrust trajectory optimization program (InTrance). During the transfer from Earth to the first target, the spacecraft is propelled by two RIT-22 ion engines from EADS Astrium, whereas a single RIT-15 is used for transfers within the Trojan region to reduce the required power. For power generation, the spacecraft uses a multi-junction solar array that is supported by concentrators. To achieve moderate mission costs, we have restricted the launch mass to a maximum of 1600 kg, the maximum interplanetary injection capability of a Soyuz/Fregat launcher. Our final layout has a mass of 1400 kg, yielding a margin of about 14%. Nestor (a member of the L4-population) was determined as the first mission target. It can be reached within 4.6 years from launch. The fuel mass ratio for this transfer is about 35%. The stay time at Nestor is 1.2 years. Eurymedon was selected as the second target (transfer time 3.5 years, stay time 3.0 years) and Irus as the third target (transfer time 2.2 years). The transfers within the Trojan L4-population can be accomplished with fuel mass ratios of about 3% for each trajectory leg. Including the stay times in orbit

  6. The design of an ultra-thin and multiple channels optical receiving antenna system with freeform lenses

    NASA Astrophysics Data System (ADS)

    Zhang, Lingyun; Cheng, Dewen; Hu, Yuan; Song, Weitao; Wang, Yongtian

    2014-11-01

    Visible Light Communications (VLC) has become an emerging area of research since it can provide higher data transmission speed and wider bandwidth. The white LEDs are very important components of the VLC system, because it has the advantages of higher brightness, lower power consumption, and a longer lifetime. More importantly, their intensity and color are modulatable. Besides the light source, the optical antenna system also plays a very important role in the VLC system since it determines the optical gain, effective working area and transmission rate of the VLC system. In this paper, we propose to design an ultra-thin and multiple channels optical antenna system by tiling multiple off-axis lenses, each of which consists of two reflective and two refractive freeform surfaces. The tiling of multiple systems and detectors but with different band filters makes it possible to design a wavelength division multiplexing VLC system to highly improve the system capacity. The field of view of the designed antenna system is 30°, the entrance pupil diameter is 1.5mm, and the thickness of the system is under 4mm. The design methods are presented and the results are discussed in the last section of this paper. Besides the optical gain is analyzed and calculated. The antenna system can be tiled up to four channels but without the increase of thickness.

  7. DS-OPTIMAL DESIGNS FOR STUDYING COMBINATIONS OF CHEMICALS USING MULTIPLE FIXED-RATIO RAY EXPERIMENTS

    EPA Science Inventory

    ABSTRACT

    Detecting and characterizing interactions among chemicals is an important environmental issue. Traditional factorial designs become infeasible as the number of compounds under study increases. Ray designs, which reduce the amount of experimental effort, can be...

  8. DS-OPTIMAL DESIGNS FOR STUDYING COMBINATIONS OF CHEMICALS USING MULTIPLE FIXED-RATIO RAY EXPERIMENTS

    EPA Science Inventory

    ABSTRACT

    Detecting and characterizing interactions among chemicals is an important environmental issue. Traditional factorial designs become infeasible as the number of compounds under study increases. Ray designs, which reduce the amount of experimental effort, can be...

  9. Detectability models and waveform design for multiple access Low-Probability-of-Intercept networks

    NASA Astrophysics Data System (ADS)

    Mills, Robert F.

    1994-04-01

    Increased connectivity demands in the tactical battlefield have led to the development of multiple access low probability-of-intercept (LPI) communication networks. Most detectability studies of LPI networks have focused on the individual network links, in which detectability calculations are carried out for a single network emitter. This report, however, presents a different approach to network detectability analysis: it is assumed that the interceptor does not attempt to distinguish one emitter from another, but rather decides only if a network is operating or not. What distinguishes this approach from conventional link intercept analysis is that detection decisions are based on energy received from multiple sources. The following multiple access schemes are considered: frequency division, time division, direct sequence code division, and frequency hop code division. The wideband radiometer and its hybrids, such as the channelized radiometer, are used as potential network intercept receivers.

  10. Design of pulse waveform for waveform division multiple access UWB wireless communication system.

    PubMed

    Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui; Wu, Zhilu

    2014-01-01

    A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study.

  11. Controller design for a class of nonlinear MIMO coupled system using multiple models and second level adaptation.

    PubMed

    Pandey, Vinay Kumar; Kar, Indrani; Mahanta, Chitralekha

    2017-07-01

    In this paper, an adaptive control method using multiple models with second level adaptation is proposed for a class of nonlinear multi-input multi-output (MIMO) coupled systems. Multiple estimation models are used to tune the unknown parameters at the first level. The second level adaptation provides a single parameter vector for the controller. A feedback linearization technique is used to design a state feedback control. The efficacy of the designed controller is validated by conducting real time experiment on a laboratory setup of twin rotor MIMO system (TRMS). The TRMS setup is discussed in detail and the experiments were performed for regulation and tracking problem for pitch and yaw control using different reference signals. An Extended Kalman Filter (EKF) has been used to observe the unavailable states of the TRMS. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Development of a multiple-parameter nonlinear perturbation procedure for transonic turbomachinery flows: Preliminary application to design/optimization problems

    NASA Technical Reports Server (NTRS)

    Stahara, S. S.; Elliott, J. P.; Spreiter, J. R.

    1983-01-01

    An investigation was conducted to continue the development of perturbation procedures and associated computational codes for rapidly determining approximations to nonlinear flow solutions, with the purpose of establishing a method for minimizing computational requirements associated with parametric design studies of transonic flows in turbomachines. The results reported here concern the extension of the previously developed successful method for single parameter perturbations to simultaneous multiple-parameter perturbations, and the preliminary application of the multiple-parameter procedure in combination with an optimization method to blade design/optimization problem. In order to provide as severe a test as possible of the method, attention is focused in particular on transonic flows which are highly supercritical. Flows past both isolated blades and compressor cascades, involving simultaneous changes in both flow and geometric parameters, are considered. Comparisons with the corresponding exact nonlinear solutions display remarkable accuracy and range of validity, in direct correspondence with previous results for single-parameter perturbations.

  13. Design and Analysis of a Forging Die for Manufacturing of Multiple Connecting Rods

    NASA Astrophysics Data System (ADS)

    Megharaj, C. E.; Nagaraj, P. M.; Jeelan Pasha, K.

    2016-09-01

    This paper demonstrates to utilize the hammer capacity by modifying the die design such that forging hammer can manufacture more than one connecting rod in a given forging cycle time. To modify the die design study is carried out to understand the parameters that are required for forging die design. By considering these parameters, forging die is designed using design modelling tool solid edge. This new design now can produce two connecting rods in same capacity hammer. The new design is required to validate by verifying complete filing of metal in die cavities without any defects in it. To verify this, analysis tool DEFORM 3D is used in this project. Before start of validation process it is require to convert 3D generated models in to. STL file format to import the models into the analysis tool DEFORM 3D. After importing these designs they are analysed for material flow into the cavities and energy required to produce two connecting rods in new forging die design. It is found that the forging die design is proper without any defects and also energy graph shows that the forging energy required to produce two connecting rods is within the limit of that hammer capacity. Implementation of this project increases the production of connecting rods by 200% in less than previous cycle time.

  14. Design of multiple-layer microwave absorbing structure based on rice husk and carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Seng, Lee Yeng; Wee, F. H.; Rahim, H. A.; AbdulMalek, MohamedFareq; You, Y. K.; Liyana, Z.; Ezanuddin, A. A. M.

    2017-01-01

    This paper presents a multiple-layered microwave absorber using rice husk and carbon nanotube composite. The dielectric properties of each layer composite were measured and analysed. The different layer of microwave absorber enables to control the microwave absorption performance. The microwave absorption performances are demonstrated through measurements of reflectivity over the frequency range 2-18 GHz. An improvement of microwave absorption <-20 dB is observed with respect to a high lossy composite placed at bottom layer of multiple layers. Reflectivity evaluations indicate that the composites display a great potential application as wideband electromagnetic wave absorbers.

  15. Optimal design of an irregular Fresnel lens for multiple light sources using a three-layered Hierarchical Genetic Algorithm.

    PubMed

    Chen, Wen-Gong; Uang, Chii-Maw; Jou, Chen-Hai

    2007-08-06

    A two-layered Hierarchical Genetic Algorithm (HGA) was proposed in a previous paper to solve the design problem of a large scale Fresnel lens used in a multiple-source lighting system. The research objective of this paper is to extend the previous work by utilizing a three-layered HGA. The goal of the suggested approach is to decrease the reliance on deciding the number of groove segments for the designed Fresnel lenses, as well as to increase the variety of groove angles in a segment to improve the performance of the designed Fresnel lens. The proposed algorithm will be applied on a simulated reading light system, and the simulation results demonstrate that the proposed approach not only makes the design of a large scale Fresnel lens more feasible but also works better than the previous one in both illuminance and uniformity for a simulated reading light system.

  16. Voltage-tolerant circuit design for fully CMOS-compatible differential multiple-time programmable nonvolatile memories

    NASA Astrophysics Data System (ADS)

    Wu, Chia-You; Lin, Hongchin; Chiu, Hou-Jen

    2017-04-01

    In this paper, a fully CMOS-compatible differential multiple-time programmable (DFMTP) nonvolatile memory (NVM) circuit, fabricated by the standard TSMC 0.18 µm CMOS process without violating the design and electrical rules, is proposed. Novel voltage-tolerant circuits were designed using the standard 3.3 and 1.8 V devices for the bit line (BL) and control gate (CG) drivers for ‑3 and 6 V program/erase operations, as well as the negative voltage isolation circuits for sense amplifiers. The DFMTP array with these voltage-tolerant control circuits was used and measured to confirm the correct program/erase/read operations.

  17. An experimental 20/30 GHz communications satellite conceptual design employing multiple-beam paraboloid reflector antennas

    NASA Technical Reports Server (NTRS)

    Goldman, A. M., Jr.

    1980-01-01

    An experimental 20/30 GHz communications satellite conceptual design is described which employs multiple-beam paraboloid reflector antennas coupled to a TDMA transponder. It is shown that the satellite employs solid state GaAs FET power amplifiers and low noise amplifiers while signal processing and switching takes place on-board the spacecraft. The proposed areas to be served by this satellite would be the continental U.S. plus Alaska, Hawaii, Puerto Rico, and the Virgin Islands, as well as southern Canada and Mexico City. Finally, attention is given to the earth stations which are designed to be low cost.

  18. An experimental 20/30 GHz communications satellite conceptual design employing multiple-beam paraboloid reflector antennas

    NASA Technical Reports Server (NTRS)

    Goldman, A. M., Jr.

    1980-01-01

    An experimental 20/30 GHz communications satellite conceptual design is described which employs multiple-beam paraboloid reflector antennas coupled to a TDMA transponder. It is shown that the satellite employs solid state GaAs FET power amplifiers and low noise amplifiers while signal processing and switching takes place on-board the spacecraft. The proposed areas to be served by this satellite would be the continental U.S. plus Alaska, Hawaii, Puerto Rico, and the Virgin Islands, as well as southern Canada and Mexico City. Finally, attention is given to the earth stations which are designed to be low cost.

  19. Simultaneous Multiple Control Force Exertion Capabilities of Males and Females versus Helicopter Control Force Design Limits,

    DTIC Science & Technology

    1987-09-01

    percent) than for collective inputs ( typically 20-35 percent). Substantial proportions of the subjects (approximately 50 percent of the males and more ...nearly 86 percent of the females performed one or more exertions below the design limit. The exertions of 28.6 percent of the females were below the pedal...design limit for more than one-half of the 16 exertions they performed; 75 percent of the exertions by 6 of the 63 females were below design-limit

  20. A multiple-alignment based primer design algorithm for genetically highly variable DNA targets

    PubMed Central

    2013-01-01

    Background Primer design for highly variable DNA sequences is difficult, and experimental success requires attention to many interacting constraints. The advent of next-generation sequencing methods allows the investigation of rare variants otherwise hidden deep in large populations, but requires attention to population diversity and primer localization in relatively conserved regions, in addition to recognized constraints typically considered in primer design. Results Design constraints include degenerate sites to maximize population coverage, matching of melting temperatures, optimizing de novo sequence length, finding optimal bio-barcodes to allow efficient downstream analyses, and minimizing risk of dimerization. To facilitate primer design addressing these and other constraints, we created a novel computer program (PrimerDesign) that automates this complex procedure. We show its powers and limitations and give examples of successful designs for the analysis of HIV-1 populations. Conclusions PrimerDesign is useful for researchers who want to design DNA primers and probes for analyzing highly variable DNA populations. It can be used to design primers for PCR, RT-PCR, Sanger sequencing, next-generation sequencing, and other experimental protocols targeting highly variable DNA samples. PMID:23965160

  1. A multiple-alignment based primer design algorithm for genetically highly variable DNA targets.

    PubMed

    Brodin, Johanna; Krishnamoorthy, Mohan; Athreya, Gayathri; Fischer, Will; Hraber, Peter; Gleasner, Cheryl; Green, Lance; Korber, Bette; Leitner, Thomas

    2013-08-21

    Primer design for highly variable DNA sequences is difficult, and experimental success requires attention to many interacting constraints. The advent of next-generation sequencing methods allows the investigation of rare variants otherwise hidden deep in large populations, but requires attention to population diversity and primer localization in relatively conserved regions, in addition to recognized constraints typically considered in primer design. Design constraints include degenerate sites to maximize population coverage, matching of melting temperatures, optimizing de novo sequence length, finding optimal bio-barcodes to allow efficient downstream analyses, and minimizing risk of dimerization. To facilitate primer design addressing these and other constraints, we created a novel computer program (PrimerDesign) that automates this complex procedure. We show its powers and limitations and give examples of successful designs for the analysis of HIV-1 populations. PrimerDesign is useful for researchers who want to design DNA primers and probes for analyzing highly variable DNA populations. It can be used to design primers for PCR, RT-PCR, Sanger sequencing, next-generation sequencing, and other experimental protocols targeting highly variable DNA samples.

  2. Multiple Choice Questions Can Be Designed or Revised to Challenge Learners' Critical Thinking

    ERIC Educational Resources Information Center

    Tractenberg, Rochelle E.; Gushta, Matthew M.; Mulroney, Susan E.; Weissinger, Peggy A.

    2013-01-01

    Multiple choice (MC) questions from a graduate physiology course were evaluated by cognitive-psychology (but not physiology) experts, and analyzed statistically, in order to test the independence of content expertise and cognitive complexity ratings of MC items. Integration of higher order thinking into MC exams is important, but widely known to…

  3. The Utilizations of Concrete, Functional, and Designative Concepts in Multiple Classification.

    ERIC Educational Resources Information Center

    Parker, Ronald K.; Halbrook, Mary Carol

    In order to investigate developmental changes in multiple classification, a matrix task was administered to 80 kindergarten first, second, and third grade children. Correct solution of the incomplete matrices, comprised of three pictures in a row and three pictures in a column meeting at a blank intersection, required identification and…

  4. Multiple Choice Questions Can Be Designed or Revised to Challenge Learners' Critical Thinking

    ERIC Educational Resources Information Center

    Tractenberg, Rochelle E.; Gushta, Matthew M.; Mulroney, Susan E.; Weissinger, Peggy A.

    2013-01-01

    Multiple choice (MC) questions from a graduate physiology course were evaluated by cognitive-psychology (but not physiology) experts, and analyzed statistically, in order to test the independence of content expertise and cognitive complexity ratings of MC items. Integration of higher order thinking into MC exams is important, but widely known to…

  5. SOUND SURVEY DESIGNS CAN FACILITATE INTEGRATING STREAM MONITORING DATA ACROSS MULTIPLE PROGRAMS

    EPA Science Inventory

    Multiple agencies in the Pacific Northwest monitor the condition of stream networks or their watersheds. Some agencies use a stream "network" perspective to report on the fraction or length of the network that either meets or violates particular criteria. Other agencies use a "wa...

  6. A Standardized Mean Difference Effect Size for Multiple Baseline Designs across Individuals

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.

    2013-01-01

    Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and…

  7. Analyzing Regression-Discontinuity Designs with Multiple Assignment Variables: A Comparative Study of Four Estimation Methods

    ERIC Educational Resources Information Center

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2013-01-01

    In a traditional regression-discontinuity design (RDD), units are assigned to treatment on the basis of a cutoff score and a continuous assignment variable. The treatment effect is measured at a single cutoff location along the assignment variable. This article introduces the multivariate regression-discontinuity design (MRDD), where multiple…

  8. Joint QTL linkage mapping for multiple-cross mating design sharing one common parent

    USDA-ARS?s Scientific Manuscript database

    Nested association mapping (NAM) is a novel genetic mating design that combines the advantages of linkage analysis and association mapping. This design provides opportunities to study the inheritance of complex traits, but also requires more advanced statistical methods. In this paper, we present th...

  9. Analyzing Regression-Discontinuity Designs with Multiple Assignment Variables: A Comparative Study of Four Estimation Methods

    ERIC Educational Resources Information Center

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2013-01-01

    In a traditional regression-discontinuity design (RDD), units are assigned to treatment on the basis of a cutoff score and a continuous assignment variable. The treatment effect is measured at a single cutoff location along the assignment variable. This article introduces the multivariate regression-discontinuity design (MRDD), where multiple…

  10. A Standardized Mean Difference Effect Size for Multiple Baseline Designs across Individuals

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.

    2013-01-01

    Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and…

  11. Experimental design and multiple response optimization. Using the desirability function in analytical methods development.

    PubMed

    Candioti, Luciana Vera; De Zan, María M; Cámara, María S; Goicoechea, Héctor C

    2014-06-01

    A review about the application of response surface methodology (RSM) when several responses have to be simultaneously optimized in the field of analytical methods development is presented. Several critical issues like response transformation, multiple response optimization and modeling with least squares and artificial neural networks are discussed. Most recent analytical applications are presented in the context of analytLaboratorio de Control de Calidad de Medicamentos (LCCM), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, S3000ZAA Santa Fe, ArgentinaLaboratorio de Control de Calidad de Medicamentos (LCCM), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, S3000ZAA Santa Fe, Argentinaical methods development, especially in multiple response optimization procedures using the desirability function.

  12. Design and use of multiple blade slurry sawing in a production atmosphere

    NASA Technical Reports Server (NTRS)

    Lynah, F. P., Jr.; Ross, J. B.

    1982-01-01

    The technique and uses of the multiple blade slurry (MBS) saw are considered. Multiple bands of steel are arranged in a frame and the frame is reciprocated with the steel bands to a workpiece, while simultaneously applying abrasive at the point of contact. The blades wear slots in the workpiece and progress through the piece resulting in several parts of wafers. The transition to MBA from diamond slicing is justified by savings resulting from minimized kerf losses, minimized subsurface damage, and improved surface quality off the saw. This allows wafering much closer to finished thickness specifications. The current state of the art MBS technology must be significantly improved if the low cost solar array (LSA) goals are to be attained. It is concluded that although MBS will never be the answer to every wafering requirement, the economical production of wafers to LSA project specifications will be achieved.

  13. Design and performance of beam test electronics for the PHENIX Multiplicity Vertex Detector

    SciTech Connect

    Britton, C.L. Jr.; Bryan, W.L.; Emery, M.S.

    1996-12-31

    The system architecture and test results of the custom circuits and beam test system for the Multiplicity-Vertex Detector (MVD) for the PHENIX detector collaboration at the Relativistic Heavy Ion Collider (RHIC) are presented in this paper. The final detector per-channel signal processing chain will consist of a preamplifier-gain stage, a current-mode summed multiplicity discriminator, a 64-deep analog memory (simultaneous read-write), a post-memory analog correlator, and a 10-bit 5 {mu}s ADC. The Heap Manager provides all timing control, data buffering, and data formatting for a single 256-channel multi-chip module (MCM). Each chip set is partitioned into 32-channel sets. Beam test (16-cell deep memory) performance for the various blocks will be presented as well as the ionizing radiation damage performance of the 1.2 {mu} n-well CMOS process used for preamplifier fabrication.

  14. Pomalidomide in the treatment of multiple myeloma: design, development and place in therapy.

    PubMed

    Ríos-Tamayo, Rafael; Martín-García, Agustín; Alarcón-Payer, Carolina; Sánchez-Rodríguez, Dolores; de la Guardia, Ana María Del Valle Díaz; García Collado, Carlos Gustavo; Jiménez Morales, Alberto; Jurado Chacón, Manuel; Cabeza Barrera, José

    2017-01-01

    Multiple myeloma is a very heterogeneous disease with variable survival. Despite recent progress and the widespread use of new agents, patients with relapsed and refractory disease have a poor outcome. Immunomodulatory drugs play a key role in both the front-line and the relapsed/refractory setting. The combination of pomalidomide (POM) and dexamethasone is safe and effective in relapsed and refractory patients, even in those with high-risk cytogenetic features. Furthermore, it can be used in most patients without the need to adjust according to the degree of renal failure. In order to further improve the results, POM-based triplet therapies are currently used. This article highlights the most relevant issues of POM and POM-based combinations in the relapsed/refractory multiple myeloma setting, from a pharmacological and clinical point of view.

  15. Pomalidomide in the treatment of multiple myeloma: design, development and place in therapy

    PubMed Central

    Ríos-Tamayo, Rafael; Martín-García, Agustín; Alarcón-Payer, Carolina; Sánchez-Rodríguez, Dolores; de la Guardia, Ana María del Valle Díaz; García Collado, Carlos Gustavo; Jiménez Morales, Alberto; Jurado Chacón, Manuel; Cabeza Barrera, José

    2017-01-01

    Multiple myeloma is a very heterogeneous disease with variable survival. Despite recent progress and the widespread use of new agents, patients with relapsed and refractory disease have a poor outcome. Immunomodulatory drugs play a key role in both the front-line and the relapsed/refractory setting. The combination of pomalidomide (POM) and dexamethasone is safe and effective in relapsed and refractory patients, even in those with high-risk cytogenetic features. Furthermore, it can be used in most patients without the need to adjust according to the degree of renal failure. In order to further improve the results, POM-based triplet therapies are currently used. This article highlights the most relevant issues of POM and POM-based combinations in the relapsed/refractory multiple myeloma setting, from a pharmacological and clinical point of view. PMID:28860711

  16. Design Decision Making With Multiple Interacting Criteria and Varying Relative Weights

    DTIC Science & Technology

    1989-07-01

    Multiattribute Utility Theory and Applications" in Multiple Criteria Decision Making, Starr and Zeleney (Eds.), TIMS Studies in Management Sciences, Vol...6, Amsterdam, North- Holland, 1977. "Advances in Multiattribute Utility Theory ," Theo a Dci, 12 (1980), 381-394. Feller, William. An Introduction to... Multiattributed Utility Function," Sloan Management Review, 14 (1972), 37-50. "Concepts of Independence in Multiattribute Utility Theory

  17. FireProt: Energy- and Evolution-Based Computational Design of Thermostable Multiple-Point Mutants

    PubMed Central

    Sebestova, Eva; Bendl, Jaroslav; Khare, Sagar; Chaloupkova, Radka; Prokop, Zbynek; Brezovsky, Jan; Baker, David; Damborsky, Jiri

    2015-01-01

    There is great interest in increasing proteins’ stability to enhance their utility as biocatalysts, therapeutics, diagnostics and nanomaterials. Directed evolution is a powerful, but experimentally strenuous approach. Computational methods offer attractive alternatives. However, due to the limited reliability of predictions and potentially antagonistic effects of substitutions, only single-point mutations are usually predicted in silico, experimentally verified and then recombined in multiple-point mutants. Thus, substantial screening is still required. Here we present FireProt, a robust computational strategy for predicting highly stable multiple-point mutants that combines energy- and evolution-based approaches with smart filtering to identify additive stabilizing mutations. FireProt’s reliability and applicability was demonstrated by validating its predictions against 656 mutations from the ProTherm database. We demonstrate that thermostability of the model enzymes haloalkane dehalogenase DhaA and γ-hexachlorocyclohexane dehydrochlorinase LinA can be substantially increased (ΔT m = 24°C and 21°C) by constructing and characterizing only a handful of multiple-point mutants. FireProt can be applied to any protein for which a tertiary structure and homologous sequences are available, and will facilitate the rapid development of robust proteins for biomedical and biotechnological applications. PMID:26529612

  18. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Low-Thrust Mission Design

    NASA Technical Reports Server (NTRS)

    Englander, Jacob A.; Vavrina, Matthew A.; Ghosh, Alexander R.

    2015-01-01

    Preliminary design of low-thrust interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys, the bodies at which those flybys are performed, and in some cases the final destination. In addition, a time-history of control variables must be chosen that defines the trajectory. There are often many thousands, if not millions, of possible trajectories to be evaluated. The customer who commissions a trajectory design is not usually interested in a point solution, but rather the exploration of the trade space of trajectories between several different objective functions. This can be a very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the mission design problem as a multi-objective hybrid optimal control problem. The method is demonstrated on a hypothetical mission to the main asteroid belt.

  19. Design, fabrication, and testing of micro-optical sensors containing multiple aspheres

    NASA Astrophysics Data System (ADS)

    Rajic, Slobodan; Egert, Charles M.; Evans, Boyd M., III; Cunningham, Joseph P.; Marlar, Troy A.

    1995-09-01

    The micro-sensor field is presently proliferating with designs and approaches. We have developed a micro-spectrometer for sensing applications containing five precision surfaces, including two off-axis aspheres. The entire monolith is less than six cubic centimeters in volume. This particular design contains a bandwidth of about 2 micrometers which is centered at 980 nm. Once an appropriate starting substrate was produced, the entire system was diamond turned to maintain the required surface figure, inter-surface spacing, and surface tilts. Only three diamond turned fixtures were needed to produce the monolith. The results proved to be more than adequate for many sensing applications. Slightly altered designs could easily be produced containing different bandwidths and resolutions as needed by the customer. Due to the spectrum of interest and the fabrication method, PMMA was the material chosen for this sensor. Other designs configurations incorporating BK7 and sapphire are presently being studied.

  20. Flexible learning in the periodic system with multiple representations: The design of a hypertext for learning complex concepts in chemistry

    NASA Astrophysics Data System (ADS)

    Mishra, Punyashloke

    1998-12-01

    This dissertation attempts to understand the complete process of instructional software design by looking closely at one iteration of the development of an educational computer program. FLiPS (Flexible Learning In the Periodic System) is a World Wide Web based multi-media hypertext for learning complex concepts in chemistry related to the periodic system of elements. The process of design begins with a theoretical argument for seeing the periodic system of elements as being a complex and ill-structured domain. A significant aspect of this argument is the introduction of certain non-standard representations of the periodic system and a demonstration of how these representations emphasize different aspects of the complex relationships between elements. The design of FLiPS is based on Cognitive Flexibility Theory---a cognitive theory that emphasizes the use of multiple representations for advanced learning in complex domains. A detailed analysis of the process of design of FLiPS is offered within the context of significant themes/perspectives on the design process. A significant part of the process of design is studying the manner in which different users interact and learn with FLiPS. Multiple means of data collection are used to understand the patterns of interaction and the cognitive processes of four students as they worked with FLiPS. This data is used to construct rich narrative profiles of the individual students: their backgrounds, beliefs, and process of working and learning. Analysis indicates that the importance of FLiPS as a learning tool seems to be dependent on the ontological and epistemological beliefs of the participants. This data is also used to generate recommendations for the further development of FLiPS. This dissertation argues that the design of technological artifacts such as educational software is a complex process involving a continuous dialogue between theory and practice; between constraints and tradeoffs; between designers and their

  1. Designing Websites for Displaying Large Data Sets and Images on Multiple Platforms

    NASA Astrophysics Data System (ADS)

    Anderson, A.; Wolf, V. G.; Garron, J.; Kirschner, M.

    2012-12-01

    The desire to build websites to analyze and display ever increasing amounts of scientific data and images pushes for web site designs which utilize large displays, and to use the display area as efficiently as possible. Yet, scientists and users of their data are increasingly wishing to access these websites in the field and on mobile devices. This results in the need to develop websites that can support a wide range of devices and screen sizes, and to optimally use whatever display area is available. Historically, designers have addressed this issue by building two websites; one for mobile devices, and one for desktop environments, resulting in increased cost, duplicity of work, and longer development times. Recent advancements in web design technology and techniques have evolved which allow for the development of a single website that dynamically adjusts to the type of device being used to browse the website (smartphone, tablet, desktop). In addition they provide the opportunity to truly optimize whatever display area is available. HTML5 and CSS3 give web designers media query statements which allow design style sheets to be aware of the size of the display being used, and to format web content differently based upon the queried response. Web elements can be rendered in a different size, position, or even removed from the display entirely, based upon the size of the display area. Using HTML5/CSS3 media queries in this manner is referred to as "Responsive Web Design" (RWD). RWD in combination with technologies such as LESS and Twitter Bootstrap allow the web designer to build web sites which not only dynamically respond to the browser display size being used, but to do so in very controlled and intelligent ways, ensuring that good layout and graphic design principles are followed while doing so. At the University of Alaska Fairbanks, the Alaska Satellite Facility SAR Data Center (ASF) recently redesigned their popular Vertex application and converted it from a

  2. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Interplanetary Mission Design Using Chemical Propulsion

    NASA Technical Reports Server (NTRS)

    Englander, Jacob A.; Vavrina, Matthew A.

    2015-01-01

    Preliminary design of high-thrust interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys and the bodies at which those flybys are performed. For some missions, such as surveys of small bodies, the mission designer also contributes to target selection. In addition, real-valued decision variables, such as launch epoch, flight times, maneuver and flyby epochs, and flyby altitudes must be chosen. There are often many thousands of possible trajectories to be evaluated. The customer who commissions a trajectory design is not usually interested in a point solution, but rather the exploration of the trade space of trajectories between several different objective functions. This can be a very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the impulsive mission design problem as a multiobjective hybrid optimal control problem. The method is demonstrated on several real-world problems.

  3. Designing a multiple dependent state sampling plan based on the coefficient of variation.

    PubMed

    Yan, Aijun; Liu, Sanyang; Dong, Xiaojuan

    2016-01-01

    A multiple dependent state (MDS) sampling plan is developed based on the coefficient of variation of the quality characteristic which follows a normal distribution with unknown mean and variance. The optimal plan parameters of the proposed plan are solved by a nonlinear optimization model, which satisfies the given producer's risk and consumer's risk at the same time and minimizes the sample size required for inspection. The advantages of the proposed MDS sampling plan over the existing single sampling plan are discussed. Finally an example is given to illustrate the proposed plan.

  4. Optically driven Archimedes micro-screws for micropump applications: multiple blade design

    NASA Astrophysics Data System (ADS)

    Baldeck, Patrice L.; Lin, Chih-Lang; Lin, Yu-Sheng; Lin, Chin-Te; Chung, Tien-Tung; Bouriau, Michel; Vitrant, Guy

    2011-10-01

    We study the rotation of photo-driven Archimedes screw with multiple blades. The micron-sized Archimedes screws are readily made by the two-photon polymerization technique. Free-floating screws that are trapped by optical tweezers align in the laser irradiation direction, and rotate spontaneously. In this study we demonstrate that the rotation speeds of two-blade-screws is twice the rotation speed of one-blade-screw. However, more complex 3-blade-screws rotate slower than 2-blade-screws due to their limited geometry resolution at this micron scale.

  5. Dynamic/Jitter Assessment of Multiple Potential HabEx Structural Designs

    NASA Technical Reports Server (NTRS)

    Knight, J. Brent; Stahl, H. Philip; Singleton, Andy; Hunt, Ron; Therrell, Melissa; Caldwell, Kate; Garcia, Jay; Baysinger, Mike

    2017-01-01

    One of the driving structural requirements of the Habitable Exo-Planet (HabEx) telescope is to maintain Line Of Sight (LOS) stability between the Primary Mirror (PM) and Secondary Mirror (SM) of = 5 mas. Dynamic analyses of two configurations of a proposed (HabEx) 4 meter off-axis telescope structure were performed to predict effects of jitter on primary/secondary mirror alignment. The dynamic disturbance used as the forcing function was the James Webb Space Telescope reaction wheel assembly vibration emission specification level. The objective of these analyses was to predict "order-of-magnitude" performance for various structural configurations which will roll into efforts to define the HabEx structural design's global architecture. Two variations of the basic architectural design were analyzed. Relative motion between the PM and the SM for each design configuration are reported.

  6. Design and Integration of an All-Magnetic Attitude Control System for FASTSAT-HSV01's Multiple Pointing Objectives

    NASA Technical Reports Server (NTRS)

    DeKock, Brandon; Sanders, Devon; Vanzwieten, Tannen; Capo-Lugo, Pedro

    2011-01-01

    The FASTSAT-HSV01 spacecraft is a microsatellite with magnetic torque rods as it sole attitude control actuator. FASTSAT s multiple payloads and mission functions require the Attitude Control System (ACS) to maintain Local Vertical Local Horizontal (LVLH)-referenced attitudes without spin-stabilization, while the pointing errors for some attitudes be significantly smaller than the previous best-demonstrated for this type of control system. The mission requires the ACS to hold multiple stable, unstable, and non-equilibrium attitudes, as well as eject a 3U CubeSat from an onboard P-POD and recover from the ensuing tumble. This paper describes the Attitude Control System, the reasons for design choices, how the ACS integrates with the rest of the spacecraft, and gives recommendations for potential future applications of the work.

  7. Multiple-bunch-length operating mode design for a storage ring using hybrid low alpha and harmonic cavity method

    NASA Astrophysics Data System (ADS)

    Gao, Weiwei; Wang, Lin; Li, Heting

    2017-03-01

    In this paper we design a simultaneous three bunch length operating mode at the HLS-II (Hefei Light Source II) storage ring by installing two harmonic cavities and minimizing the momentum compaction factor. The short bunches (2.6 mm) presented in this work will meet the requirement of coherent millimeter-wave and sub-THz radiation experiments, while the long bunches (20 mm) will efficiently increase the total beam current. Therefore, this multiple-bunch-length operating mode allows present synchrotron users and coherent millimeter-wave users (or sub THz users) to carry out their experiments simultaneously. Since the relatively low energy characteristic of HLS-II we achieve the multiple-bunch-length operating mode without multicell superconducting RF cavities, which is technically feasible.

  8. Multiple-shot ultraviolet laser damage resistance of nonquarterwave reflector designs for 248 NM

    SciTech Connect

    Newnam, B.E.; Foltyn, S.R.; Jolin, L.J.

    1982-01-01

    The damage resistance of multilayer dielectric reflectors designed for 248 nm has been substantially increased by use of nonquarterwave (QW) thicknesses for the top few layers. These designs minimize the peak standing-wave electric field in the high-index layers, which have proven to be weaker than the low-index components. Previous damage tests of infrared- and visible-wavelength reflectors based on these designs have produced variable results. However, at the ultraviolet wavelength of 248 nm, 99% reflectors of Sc/sub 2/O/sub 3/, MgF/sub 2/, and SiO/sub 2/ strongly demonstrated the merit of non-QW designs. Four sets of reflectors of each of four designs (all QW thickness; one modified-pair substitution; two modified-pair substitution; one modified pair plus an extra half-wave layer of Sc/sub 2/O/sub 3/) were tested for damage resistance with a KrF laser operating at 35 pps with a pulsewidth of 8 ns and spot-size diameter of 0.6 mm. Each of 50 sites were irradiated for 1000 shots or until damage occurred. On the average, the reflectors with one-modified-thickness pair had a 50% higher threshold (10 to 10 sites survived) than the all-quarterwave design. Addition of a second modified-layer pair resulted in no further increase in threshold but the saturation fluence (10 of 10 sites damage) was 110% higher. Reflectors with an additional half-wave of Sc/sub 2/O/sub 3/ had lower thresholds of the order of 10% as expected. The thresholds correlated best with peak-field models, whereas the best model correlating the saturation fluences involved the sum of the upper two scandia layer thicknesses.

  9. Multiple case studies of STEM teachers' orientations to science teaching through engineering design

    NASA Astrophysics Data System (ADS)

    Rupp, Madeline

    The following master's thesis is composed of two manuscripts describing STEM teachers' orientations to science teaching through engineering within the context of the Science Learning through Engineering Design (SLED) partnership. The framework guiding both studies was science teaching orientations, a component of pedagogical content knowledge. Data were collected via semi-structured interviews, multi-day classroom observations, pre- and post-observation interviews, implementation plans, and written reflections. Data sources were analyzed to generate two orientations to science teaching through engineering design for each participant. The first manuscript illustrates a single case study conducted with a sixth grade STEM teacher. Results of this study revealed a detailed picture of the teacher's goals, practices, assessments, and general views when teaching science through engineering design. Common themes across the teacher's instruction were used to characterize her orientations to science teaching through engineering design. Overall, the teacher's orientations showed a shift in her practice from didactic to student-centered methods of teaching as a result of integrating engineering design-based curriculum. The second manuscript describes a comparative case study of two sixth grade SLED participants. Results of this study revealed more complex and diverse relationships between the teachers' orientations to teaching science through engineering design and their instruction. Participants' orientations served as filters for instruction, guided by their divergent purposes for science teaching. Furthermore, their orientations and resulting implementation were developed from knowledge gained in teacher education, implying that teacher educators and researchers can use this framework to learn more about how teachers' knowledge is used to integrate engineering and science practices in the K-12 classroom.

  10. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Interplanetary Mission Design using Chemical Propulsion

    NASA Technical Reports Server (NTRS)

    Englander, Jacob A.; Vavrina, Matthew A.

    2015-01-01

    Preliminary design of high-thrust interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys and the bodies at which those flybys are performed. For some missions, such as surveys of small bodies, the mission designer also contributes to target selection. In addition, real-valued decision variables, such as launch epoch, flight times, maneuver and flyby epochs, and flyby altitudes must be chosen. There are often many thousands of possible trajectories to be evaluated. The customer who commissions a trajectory design is not usually interested in a point solution, but rather the exploration of the trade space of trajectories between several different objective functions. This can be a very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the impulsive mission design problem as a multi-objective hybrid optimal control problem. The method is demonstrated on several real-world problems. Two assumptions are frequently made to simplify the modeling of an interplanetary high-thrust trajectory during the preliminary design phase. The first assumption is that because the available thrust is high, any maneuvers performed by the spacecraft can be modeled as discrete changes in velocity. This assumption removes the need to integrate the equations of motion governing the motion of a spacecraft under thrust and allows the change in velocity to be modeled as an impulse and the expenditure of propellant to be modeled using the time-independent solution to Tsiolkovsky's rocket equation [1]. The second assumption is that the spacecraft moves primarily under the influence of the central body, i.e. the sun, and all other perturbing forces may be neglected in preliminary design. The path of the spacecraft may then be modeled as a series of conic sections. When a spacecraft performs a close

  11. Human-Centered Design and Evaluation of Haptic Cueing for Teleoperation of Multiple Mobile Robots.

    PubMed

    Son, Hyoung Il; Franchi, Antonio; Chuang, Lewis L; Kim, Junsuk; Bulthoff, Heinrich H; Giordano, Paolo Robuffo

    2013-04-01

    In this paper, we investigate the effect of haptic cueing on a human operator's performance in the field of bilateral teleoperation of multiple mobile robots, particularly multiple unmanned aerial vehicles (UAVs). Two aspects of human performance are deemed important in this area, namely, the maneuverability of mobile robots and the perceptual sensitivity of the remote environment. We introduce metrics that allow us to address these aspects in two psychophysical studies, which are reported here. Three fundamental haptic cue types were evaluated. The Force cue conveys information on the proximity of the commanded trajectory to obstacles in the remote environment. The Velocity cue represents the mismatch between the commanded and actual velocities of the UAVs and can implicitly provide a rich amount of information regarding the actual behavior of the UAVs. Finally, the Velocity+Force cue is a linear combination of the two. Our experimental results show that, while maneuverability is best supported by the Force cue feedback, perceptual sensitivity is best served by the Velocity cue feedback. In addition, we show that large gains in the haptic feedbacks do not always guarantee an enhancement in the teleoperator's performance.

  12. Design and synthesis of multiple antigenic peptides and their application for dengue diagnosis.

    PubMed

    Rai, Reeta; Dubey, Sameer; Santosh, K V; Biswas, Ashutosh; Mehrotra, Vinit; Rao, D N

    2017-09-01

    Major difficulty in development of dengue diagnostics is availability of suitable antigens. To overcome this, we made an attempt to develop a peptide based diagnosis which offers significant advantage over other methods. With the help of in silico methods, two epitopes were selected from envelope protein and three from NS1 protein of dengue virus. These were synthesized in combination as three multiple antigenic peptides (MAPs). We have tested 157 dengue positive sera confirmed for NS1 antigen. MAP1 showed 96.81% sera positive for IgM and 68.15% positive for IgG. MAP2 detected 94.90% IgM and 59.23% IgG positive sera. MAP3 also detected 96.17% IgM and 59.87% IgG positive sera. To the best of our knowledge this is the first study describing the use of synthetic multiple antigenic peptides for the diagnosis of dengue infection. This study describes MAPs as a promising tool for the use in serodiagnosis of dengue. Copyright © 2017 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  13. Estimating causal effects from multiple-baseline studies: implications for design and analysis.

    PubMed

    Ferron, John M; Moeyaert, Mariola; Van den Noortgate, Wim; Beretvas, S Natasha

    2014-12-01

    Traditionally, average causal effects from multiple-baseline data are estimated by aggregating individual causal effect estimates obtained through within-series comparisons of treatment phase trajectories to baseline extrapolations. Concern that these estimates may be biased due to event effects, such as history and maturation, motivates our proposal of a between-series estimator that contrasts participants in the treatment to those in the baseline phase. Accuracy of the new method was assessed and compared in a series of simulation studies where participants were randomly assigned to intervention start points. The within-series estimator was found to have greater power to detect treatment effects but also to be biased due to event effects, leading to faulty causal inferences. The between-series estimator remained unbiased and controlled the Type I error rate independent of event effects. Because the between-series estimator is unbiased under different assumptions, the 2 estimates complement each other, and the difference between them can be used to detect inaccuracies in the modeling assumptions. The power to detect inaccuracies associated with event effects was found to depend on the size and type of event effect. We empirically illustrate the methods using a real data set and then discuss implications for researchers planning multiple-baseline studies. PsycINFO Database Record (c) 2014 APA, all rights reserved

  14. Spreading and Interleaving Design for Synchronous Interleave-Division Multiple-Access

    NASA Astrophysics Data System (ADS)

    Song, Guanghui; Cheng, Jun; Watanabe, Yoichiro

    A K-user interleave-division multiple-access (IDMA) system with symbol-synchronous and equal-power users is considered. In this IDMA system, the spreading, interleaving, and multiple-access channel (MAC) are jointly considered as an equivalent channel, referred to as an IDMA channel. Given channel signal-to-noise ratio (SNR), the sum capacity of the IDMA channel is only determined by a K-user spread-interleave (SI) matrix. First, it is shown that to maximize the sum capacity of the IDMA channel, rows or columns of its K-user SI matrix should be pairwise orthogonal. The optimal K-user SI matrix is constructed. Second, for the IDMA system with each user employing the same spreading sequence followed by random interleaving, it is shown that, as the number of users approaches infinity, the sum capacity of the IDMA channel converges to a determinate value, which is achieved by a balanced spreading sequence. Moreover, when both the number of users and the data length approach infinity, this determinate value of sum capacity is achieved by an arbitrary spreading sequence. Furthermore, for a finite number of users, an optimal spreading sequence is derived by minimizing an expected column correlation of the K-user SI matrix. It shows that this optimal spreading sequence provides the maximum ergodic sum capacity.

  15. Modeling external events in the three-level analysis of multiple-baseline across-participants designs: a simulation study.

    PubMed

    Moeyaert, Mariola; Ugille, Maaike; Ferron, John M; Beretvas, S Natasha; Van den Noortgate, Wim

    2013-06-01

    In this study, we focus on a three-level meta-analysis for combining data from studies using multiple-baseline across-participants designs. A complicating factor in such designs is that results might be biased if the dependent variable is affected by not explicitly modeled external events, such as the illness of a teacher, an exciting class activity, or the presence of a foreign observer. In multiple-baseline designs, external effects can become apparent if they simultaneously have an effect on the outcome score(s) of the participants within a study. This study presents a method for adjusting the three-level model to external events and evaluates the appropriateness of the modified model. Therefore, we use a simulation study, and we illustrate the new approach with real data sets. The results indicate that ignoring an external event effect results in biased estimates of the treatment effects, especially when there is only a small number of studies and measurement occasions involved. The mean squared error, as well as the standard error and coverage proportion of the effect estimates, is improved with the modified model. Moreover, the adjusted model results in less biased variance estimates. If there is no external event effect, we find no differences in results between the modified and unmodified models.

  16. WV R-EMAP STUDY: MULTIPLE-OBJECTIVE SAMPLING DESIGN FRAMEWORK

    EPA Science Inventory

    A multi-objective sampling design has been implemented through Regional Monitoring and Assessment Program (R-EMAP) support of a cooperative agreement with the state of West Virginia. Goals of the project include: 1) development and testing of a temperature-adjusted fish IBI for t...

  17. Analyzing Regression-Discontinuity Designs with Multiple Assignment Variables: A Comparative Study of Four Estimation Methods

    ERIC Educational Resources Information Center

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2012-01-01

    In a traditional regression-discontinuity design (RDD), units are assigned to treatment and comparison conditions solely on the basis of a single cutoff score on a continuous assignment variable. The discontinuity in the functional form of the outcome at the cutoff represents the treatment effect, or the average treatment effect at the cutoff.…

  18. Linear regulator design for stochastic systems by a multiple time scales method

    NASA Technical Reports Server (NTRS)

    Teneketzis, D.; Sandell, N. R., Jr.

    1976-01-01

    A hierarchically-structured, suboptimal controller for a linear stochastic system composed of fast and slow subsystems is considered. The controller is optimal in the limit as the separation of time scales of the subsystems becomes infinite. The methodology is illustrated by design of a controller to suppress the phugoid and short period modes of the longitudinal dynamics of the F-8 aircraft.

  19. Orientations to Professional Development Design and Implementation: Understanding Their Relationship to PD Outcomes across Multiple Projects

    ERIC Educational Resources Information Center

    Marra, Rose M.; Arbaugh, Fran; Lannin, John; Abell, Sandra; Ehlert, Mark; Smith, Rena; Merle-Johnson, Dominike; Rogers, Meredith Park

    2011-01-01

    Given the large investment in teacher professional development (PD), further understanding of the factors that impact PD success is needed. In a previous study, the authors established a framework for categorizing PD projects using the notion of orientations. A PD orientation is comprised of project characteristics that drive the PD design and…

  20. Multiple Pathways to Learning: An Examination of Universal Design and Online Strategic Learning in Higher Education

    ERIC Educational Resources Information Center

    Hicks, Maryruth Wilks

    2010-01-01

    The purpose of this study was to examine the effectiveness of universally designed (UD) instruction on strategic learning in an online, interactive learning environment (ILE). The research focused on the premise that the customizable, media-based framework of UD instruction might influence diverse online learning strategies. This study…

  1. Multiple Pathways to Learning: An Examination of Universal Design and Online Strategic Learning in Higher Education

    ERIC Educational Resources Information Center

    Hicks, Maryruth Wilks

    2010-01-01

    The purpose of this study was to examine the effectiveness of universally designed (UD) instruction on strategic learning in an online, interactive learning environment (ILE). The research focused on the premise that the customizable, media-based framework of UD instruction might influence diverse online learning strategies. This study…

  2. Orientations to Professional Development Design and Implementation: Understanding Their Relationship to PD Outcomes across Multiple Projects

    ERIC Educational Resources Information Center

    Marra, Rose M.; Arbaugh, Fran; Lannin, John; Abell, Sandra; Ehlert, Mark; Smith, Rena; Merle-Johnson, Dominike; Rogers, Meredith Park

    2011-01-01

    Given the large investment in teacher professional development (PD), further understanding of the factors that impact PD success is needed. In a previous study, the authors established a framework for categorizing PD projects using the notion of orientations. A PD orientation is comprised of project characteristics that drive the PD design and…

  3. Design and Evaluation of a User Interface Supporting Multiple Image Query Models.

    ERIC Educational Resources Information Center

    Mostafa, Javed; Dillon, Andrew

    1996-01-01

    Describes the ViewFinder interface, designed at Indiana University as a client to a database server; it supports querying based on both visual and verbal clues. Presents results of usability analysis performed on ViewFinder with 18 users. High search success rates were achieved through both types of querying means; verbal clues were used more than…

  4. Multiple Information Failure: A Case of Different Investments in Form and Content in Graphic Design

    ERIC Educational Resources Information Center

    Barnes, Carolyn; Taffe, Simone; Miceli, Lucy

    2009-01-01

    This paper considers a sequence of failures in the design of information. It focuses on the Safe and Sustainable Indoor Cleaning study (SASI Clean), a 2007 government-funded study into cleaning practices in Australian childcare centers. Empowerment through participation was integral to the study, childcare workers being seen as collaborators in…

  5. The Generalized Regression Discontinuity Design: Using Multiple Assignment Variables and Cutoffs to Estimate Treatment Effects

    ERIC Educational Resources Information Center

    Wong, Vivian C.; Steiner, Peter M.; Cook, Thomas D.

    2009-01-01

    This paper introduces a generalization of the regression-discontinuity design (RDD). Traditionally, RDD is considered in a two-dimensional framework, with a single assignment variable and cutoff. Treatment effects are measured at a single location along the assignment variable. However, this represents a specialized (and straight-forward)…

  6. Using Engineering Design Challenges to Engage Elementary Students with Gifts and Talents across Multiple Content Areas

    ERIC Educational Resources Information Center

    Dailey, Debbie

    2017-01-01

    With the release of the Next Generation Science Standards and the adoption of the standards by many states, teachers are encouraged to use the engineering design process (EDP) as an instructional approach to teaching science. However, teachers have limited time to teach science and will often neglect science in favor of mathematics and literacy…

  7. Optimization and development of stable w/o/w cosmetic multiple emulsions by means of the Quality by Design approach.

    PubMed

    Kovács, A; Erős, I; Csóka, I

    2016-04-01

    The aim of our present work was to develop stable water-in-oil-in-water (w/o/w) cosmetic multiple emulsions that are proper for cosmetic use and can also be applied on the skin as pharmaceutical vehicles by means of Quality by Design (QbD) concept. This product design concept consists of a risk assessment step and also the 'predetermination' of the critical material attributes and process parameters of a stable multiple emulsion system. We have set up the hypothesis that the stability of multiple emulsions can be improved by the development based on such systematic planning - making a map of critical product parameters - so their industrial usage can be increased. The risk assessment and the determination of critical physical-chemical stability parameters of w/o/w multiple emulsions to define critical control points were performed by means of quality tools and the leanqbd(™) (QbD Works LLC, Fremont, CA, U.S.A.) software. Critical materials and process parameters: Based on the results of preformulation experiments, three factors, namely entrapped active agent, preparation methodology and shear rate, were found to be highly critical factors for critical quality attributes (CQAs) and for stability, whereas the nature of oil was found a medium level risk factor. The results of the risk assessment are the following: (i) droplet structure and size distribution should be evaluated together to be able to predict the stability issues, (ii) the presence of entrapped active agents had a great impact on droplet structure, (iii) the viscosity curves represent the structural changes during storage, if the decrease in relative viscosity is >15% the emulsion disintegrates, and (iv) it is enough to use the shear rate between 34g and 116g relative centrifugal force (RCF). CQAs: By risk assessment, we discovered that four factors should be considered to be high-risk variables as compared to others: droplet size, droplet structure, viscosity and multiple character were found to be

  8. Design Studies for a Multiple Application Thermal Reactor for Irradiation Experiments (MATRIX)

    SciTech Connect

    Pope, Michael A.; Gougar, Hans D.; Ryskamp, J. M.

    2015-03-01

    The Advanced Test Reactor (ATR) is a high power density test reactor specializing in fuel and materials irradiation. For more than 45 years, the ATR has provided irradiations of materials and fuels testing along with radioisotope production. Should unforeseen circumstances lead to the decommissioning of ATR, the U.S. Government would be left without a large-scale materials irradiation capability to meet the needs of its nuclear energy and naval reactor missions. In anticipation of this possibility, work was performed under the Laboratory Directed Research and Development (LDRD) program to investigate test reactor concepts that could satisfy the current missions of the ATR along with an expanded set of secondary missions. A survey was conducted in order to catalogue the anticipated needs of potential customers. Then, concepts were evaluated to fill the role for this reactor, dubbed the Multi-Application Thermal Reactor Irradiation eXperiments (MATRIX). The baseline MATRIX design is expected to be capable of longer cycle lengths than ATR given a particular batch scheme. The volume of test space in In-Pile-Tubes (IPTs) is larger in MATRIX than in ATR with comparable magnitude of neutron flux. Furthermore, MATRIX has more locations of greater volume having high fast neutron flux than ATR. From the analyses performed in this work, it appears that the lead MATRIX design can be designed to meet the anticipated needs of the ATR replacement reactor. However, this design is quite immature, and therefore any requirements currently met must be re-evaluated as the design is developed further.

  9. Design and analysis of rotor systems with multiple trailing edge flaps and resonant actuators

    NASA Astrophysics Data System (ADS)

    Kim, Jun-Sik

    The purpose of this thesis is to develop piezoelectric resonant actuation systems and new active control methods utilizing the multiple trailing-edge flaps' configuration for rotorcraft vibration suppression and blade loads control. An aeroelastic model is developed for a composite rotor blade with multiple trailing-edge flaps. The rotor blade airloads are calculated using quasi-steady blade element aerodynamics with a free wake model for rotor inflow. A compressible unsteady aerodynamics model is employed to accurately predict the incremental trailing edge flap airloads. Both the finite wing effect and actuator saturation for trailing-edge flaps are also included in an aeroelastic analysis. For a composite articulated rotor, a new active blade loads control method is developed and tested numerically. The concept involves straightening the blade by introducing dual trailing edge flaps. The objective function, which includes vibratory hub loads, bending moment harmonics and active flap control inputs, is minimized by an integrated optimal control/optimization process. A numerical simulation is performed for the steady-state forward flight of an advance ratio of 0.35. It is demonstrated that through straightening the rotor blade, which mimics the behavior of a rigid blade, both the bending moments and vibratory hub loads can be significantly reduced by 32% and 57%, respectively. An active vibration control method is developed and analyzed for a hingeless rotor. The concept involves deflecting each individual trailing-edge flap using a compact resonant actuation system. Each resonant actuation system could yield high authority, while operating at a single frequency. Parametric studies are conducted to explore the finite wing effect of trailing-edge flaps and actuator saturation. A numerical simulation has been performed for the steady-state forward flight (mu = 0.15 ˜ 0.35). It is demonstrated that multiple trailing-edge flap configuration with the resonant actuation

  10. A novel laser doppler linear encoder using multiple-reflection optical design for high-resolution linear actuator.

    SciTech Connect

    Shu, D.

    1998-07-16

    A novel laser Doppler linear encoder system (LDLE) has been developed at the Advanced Photon Source, Argonne National Laboratory. A self-aligning 3-D multiple-reflection optical design was used for the laser Doppler displacement meter (LDDM) to extend the encoder system resolution. The encoder is compact [about 70 mm(H) x 100 mm(W) x 250 mm(L)] and it has sub-Angstrom resolution, 100 mm/sec measuring speed, and 300 mm measuring range. Because the new device affords higher resolution, as compared with commercial laser interferometer systems, and yet cost less, it will have good potential for use in scientific and industrial applications.

  11. The Afferent Visual Pathway: Designing a Structural-Functional Paradigm of Multiple Sclerosis

    PubMed Central

    Costello, Fiona

    2013-01-01

    Multiple sclerosis (MS) is a disease of the central nervous system (CNS) believed to arise from a dysfunctional immune-mediated response in a genetically susceptible host. The actual cause of MS is not known, and there is ongoing debate about whether this CNS disorder is predominantly an inflammatory versus a degenerative condition. The afferent visual pathway (AVP) is frequently involved in MS, such that one in every five individuals affected presents with acute optic neuritis (ON). As a functionally eloquent system, the AVP is amenable to interrogation with highly reliable and reproducible tests that can be used to define a structural-functional paradigm of CNS injury. The AVP has numerous unique advantages as a clinical model of MS. In this review, the parameters and merits of the AVP model are highlighted. Moreover, the roles the AVP model may play in elucidating mechanisms of brain injury and repair in MS are described. PMID:24288622

  12. Design and verification of a multiple fault tolerant control system for STS applications using computer simulation

    NASA Technical Reports Server (NTRS)

    Szatkowski, G. P.; Karas, J. C.

    1981-01-01

    General Dynamics/Convair is under NASA contract to integrate the Centaur upper stage into the space transportation system for future planetary missions. This requires that control of all safety critical functions be two-failure tolerant. The control system developed consists of five asynchronous computers, each contributing at their outputs to a 3-out-of-5 voting plane. Subsystem control is based on an end function redundancy management scheme. Analysis of multiple component failures and worst-case time-phase asynchrony among the computers is performed by a real-time computer simulation. The simulation emulates the hardware and subsystem interfaces, wire by wire, providing assessibility to any component for the insertion of preprogrammed failures. Observability is provided via a graphics system and diagnostic software. The simulation provides an engineering tool where the integrity of control system hardware and imbedded software can be demonstrated.

  13. Tailored design of multiple nanoarchitectures in metal-cyanide hybrid coordination polymers.

    PubMed

    Hu, Ming; Belik, Alexei A; Imura, Masataka; Yamauchi, Yusuke

    2013-01-09

    Recently, coordination polymers (CPs) with nanoscale porosity and unique property have demonstrated great potential in many applications. Encouraged by significant progress in the controlled synthesis of nanomaterials, such as metals and semiconductors, the morphologically controlled synthesis of CPs has been considered a potential way to further enhance the inherent properties and develop new functions. In particular, hollow-based CPs are promising nanoarchitectures that can bring several properties derived from crystalline thin shells and interior cavities. Here we demonstrate an exquisite construction method to synthesize CPs with multiple hollow-based nanoarchitectures. Through step-by-step CP crystal growth and subsequent etching processes, various types of CPs with shell-in-shell, yolk-shell, and yolk-double-shell hollow structures can be synthesized for the first time. This type of nanoarchitecture is powerful for the exploration of alternative properties of CPs. The resultant hollow-based nanoarchitectures significantly increase gas adsorption and bring out interesting magnetic properties.

  14. Tradeoff-based optimization criteria in clinical trials with multiple objectives and adaptive designs.

    PubMed

    Dmitrienko, Alex; Paux, Gautier; Pulkstenis, Erik; Zhang, Jianliang

    2016-01-01

    The article discusses clinical trial optimization problems in the context of mid- to late-stage drug development. Using the Clinical Scenario Evaluation approach, main objectives of clinical trial optimization are formulated, including selection of clinically relevant optimization criteria, identification of sets of optimal and nearly optimal values of the parameters of interest, and sensitivity assessments. The paper focuses on a class of optimization criteria arising in clinical trials with several competing goals, termed tradeoff-based optimization criteria, and discusses key considerations in constructing and applying tradeoff-based criteria. The clinical trial optimization framework considered in the paper is illustrated using two case studies based on a clinical trial with multiple objectives and a two-stage clinical trial which utilizes adaptive decision rules.

  15. Multiple choice questions can be designed or revised to challenge learners' critical thinking.

    PubMed

    Tractenberg, Rochelle E; Gushta, Matthew M; Mulroney, Susan E; Weissinger, Peggy A

    2013-12-01

    Multiple choice (MC) questions from a graduate physiology course were evaluated by cognitive-psychology (but not physiology) experts, and analyzed statistically, in order to test the independence of content expertise and cognitive complexity ratings of MC items. Integration of higher order thinking into MC exams is important, but widely known to be challenging-perhaps especially when content experts must think like novices. Expertise in the domain (content) may actually impede the creation of higher-complexity items. Three cognitive psychology experts independently rated cognitive complexity for 252 multiple-choice physiology items using a six-level cognitive complexity matrix that was synthesized from the literature. Rasch modeling estimated item difficulties. The complexity ratings and difficulty estimates were then analyzed together to determine the relative contributions (and independence) of complexity and difficulty to the likelihood of correct answers on each item. Cognitive complexity was found to be statistically independent of difficulty estimates for 88 % of items. Using the complexity matrix, modifications were identified to increase some item complexities by one level, without affecting the item's difficulty. Cognitive complexity can effectively be rated by non-content experts. The six-level complexity matrix, if applied by faculty peer groups trained in cognitive complexity and without domain-specific expertise, could lead to improvements in the complexity targeted with item writing and revision. Targeting higher order thinking with MC questions can be achieved without changing item difficulties or other test characteristics, but this may be less likely if the content expert is left to assess items within their domain of expertise.

  16. Custom-designed AMLCD modules common to multiple platforms from consumer-oriented fabrication facility

    NASA Astrophysics Data System (ADS)

    Niemczyk, James

    2002-08-01

    The APC- LG-LCD relationship continues to expand with new products developed specifically for APC applications and also LG-LCD products developed for the consumer market, but adapted using APC enhancements for applications in the rugged world. Our delivery performance has proven that a superior, cost effective product can only be produced by incorporating product enhancements at the point of AMLCD manufacture. Further adaptations for specific applications can be simplified by utilizing the same part number panel for multiple platform uses. The manufacturing environment must be flexible enough to run multiple part numbers on a weekly basis. As such, manufacturing automation implemented at APC continues to strengthen our position as the world leader in custom AMLCD display modules. These automation initiatives are the direct result of APC learning the LG-LCD manufacturing method and applying these principals to our particular processes. The APC - LG-LCD relationship affords availability guarantees for display modules for a period of 10 years, thereby reducing procurement risk and minimizing costs associated with redesign when using consumer driven panels. This guarantee redefines the game rules for procurement of AMLCD's. We also offer a very quick turn for those customers who prefer to perform a lifetime buy of product. Typically, thousands of panels can be delivered within six months of a production go ahead. The APC -LC-LCD team remains successful due to the many years spent working together to develop and manufacture products that this niche market demands. The mutual respect for the technical and manufacturing operations at APC and LG-LCD continues to foster a relationship that time and again deliver superior, cost effective products to the market.

  17. Design and Characterization of Multiple Coupled Microring Based Wavelength Demultiplexer in Silicon-On (soi)

    NASA Astrophysics Data System (ADS)

    Haroon, Hazura; Shaari, Sahbudin; Menon, P. S.; Mardiana, B.; Hanim, A. R.; Arsad, N.; Majlis, B. Y.; Mukhtar, W. M.; Abdullah, Huda

    We report in this paper, an optimized design and characterization of SOI based single mode, four channels wavelength demultiplexer using microrings. The usage of silicon-on-insulator (SOI) allows a wide free spectral range (FSR) for the device that is crucial in developing ultra-compact integrations of planar lightwave circuits (PLCs). The characterizations are done using Finite-Difference Time-Domain (FDTD) mode simulations from RSOFT. Serially cascaded microring arrays up to the third order are presented to study the design trade-off among the FSR, Q-factor and optical losses of the laterally coupled wavelength demultiplexer. The demultiplexer is expected to be working at C-band region of Wavelength Division Multilplexing (WDM) for a wavelength around 1550 nm. Our proposed demultiplexer has low insertion loss (< 0.5 dB) and a crosstalk around 12 ~ 19 dB.

  18. Wide-field imaging design for a multiple-capillary DNA-sequencing system

    NASA Astrophysics Data System (ADS)

    Nay, Lyle M.; Sinclair, Robert; Swerdlow, Harold

    1997-05-01

    A laser-induced fluorescence detection system compatible with a capillary electrophoresis array was developed. The design incorporates fiber-optic excitation and a detection system including a diffraction grating and a CCD camera. The system employs no moving parts and is capable of producing data comparable to commercially available systems. It is based on a spectrally-resolved four-dye sequencing scheme. The conceptual design was proven, however, refinements must be made to optimize performance for high-throughput capillary-array DNA sequencing. Automated sample preparation and loading in combination with a refillable separation- matrix capillary-array system could prove to be an invaluable tool for completion of the Human Genome Project.

  19. Dynamic/Jitter Assessment of Multiple Potential HabEx Structural Designs

    NASA Technical Reports Server (NTRS)

    Knight, J. Brent; Stahl, H. Philip; Singleton, Andrew William; Hunt, Ronald A.; Therrell, Melissa F.; Caldwell, Mary Kathryn; Garcia, Jay Clarke

    2017-01-01

    The 2020 Decadal Survey in Astronomy and Astrophysics will assess candidate large missions to follow James Webb Space Telescope (JWST) and Wide Field Infrared Space Telescope (WFIRST). One candidate mission is the Habitable ExoPlanet Imaging Mission (HabEx). This presentation describes two HabEx structural designs and results from structural dynamic analyses performed to predict Primary Mirror (PM) Secondary Mirror (SM) Line of Site (LOS) stability (jitter) due to Reaction Wheel Assembly (RWA) vibrations.

  20. A Simple Tool for the Design and Analysis of Multiple-reflector Antennas in a Multi-disciplinary Environment

    NASA Technical Reports Server (NTRS)

    Katz, Daniel, S.; Borgioli, Andrea; Cwik, Tom; Fu, Chuigang; Imbriale, William A.; Jamnejad, Vahraz; Springer, Paul L.

    1999-01-01

    The process of designing and analyzing a multiple-reflector system has traditionally been time-intensive, requiring large amounts of both computational and human time. At many frequencies, a discrete approximation of the radiation integral may be used to model the system. The code which implements this physical optics (PO) algorithm was developed at the Jet Propulsion Laboratory. It analyzes systems of antennas in pairs, and for each pair, the analysis can be computationally time-consuming. Additionally, the antennas must be described using a local coordinate system for each antenna, which makes it difficult to integrate the design into a multi-disciplinary framework in which there is traditionally one global coordinate system, even before considering deforming the antenna as prescribed by external structural and/or thermal factors. Finally, setting up the code to correctly analyze all the antenna pairs in the system can take a fair amount of time, and introduces possible human error.

  1. Design of temperature-independent arrayed waveguide gratings based on the combination of multiple types of waveguide.

    PubMed

    Huang, Huamao; Ho, Seng-Tiong; Huang, Dexiu; Tu, Yongming; Liu, Wen

    2010-06-01

    We develop a design theory for a temperature-independent arrayed waveguide grating (TI-AWG) based on the combination of multiple types of waveguide. Each type of waveguide has a path-length difference between adjacent arrayed waveguides, and the path-length difference ratio is introduced as tuning parameter. A TI-AWG with Si wire and slot waveguides is given as an example. The thermal spectra shift of the TI-AWG can be tuned from redshift to blueshift in an ultralarge range, and the modified interference order can be reduced or enhanced. The device size is about one-fifth that of the narrow-wide-wire design that uses a combination of narrow and wide Si wire waveguides. The results are verified by the simulation of prototype devices via a two-dimensional finite-difference time-domain program.

  2. Effects of pesticides on songbird productivity in conjunction with pecan cultivation in southern Georgia: A multiple-exposure experimental design

    USGS Publications Warehouse

    Patnode, K.A.; White, D.H.

    1991-01-01

    A prototypic experimental design was used to assess sublethal effects of multiple and varied organophosphates and carbamates on reproduction in birds. The design allowed for classification of pesticide exposure according to toxicity of applied compounds and type and frequency of applications. Daily survival rates (DSRs) of nests, eggs, and nestlings were determined for northern mockingbirds (Mimus polyglottos), brown thrashers (Toxostoma rufum), and northern cardinals (Cardinalis cardinalis) nesting along edges of pecan orchards and row crops in southern Georgia [USA]. Egg and nestling DSRs for all species combined varied inversely (P 0.05) among three exposure levels. Brain cholinesterase activities were age-dependent and substantiated adult, but not nestling, exposure. Results suggest that increasing exposure to pesticides may reduce songbird productivity.

  3. A Simple Tool for the Design and Analysis of Multiple-Reflector Antennas in a Multi-Disciplinary Environment

    NASA Technical Reports Server (NTRS)

    Katz, Daniel S.; Cwik, Tom; Fu, Chuigang; Imbriale, William A.; Jamnejad, Vahraz; Springer, Paul L.; Borgioli, Andrea

    2000-01-01

    The process of designing and analyzing a multiple-reflector system has traditionally been time-intensive, requiring large amounts of both computational and human time. At many frequencies, a discrete approximation of the radiation integral may be used to model the system. The code which implements this physical optics (PO) algorithm was developed at the Jet Propulsion Laboratory. It analyzes systems of antennas in pairs, and for each pair, the analysis can be computationally time-consuming. Additionally, the antennas must be described using a local coordinate system for each antenna, which makes it difficult to integrate the design into a multi-disciplinary framework in which there is traditionally one global coordinate system, even before considering deforming the antenna as prescribed by external structural and/or thermal factors. Finally, setting up the code to correctly analyze all the antenna pairs in the system can take a fair amount of time, and introduces possible human error. The use of parallel computing to reduce the computational time required for the analysis of a given pair of antennas has been previously discussed. This paper focuses on the other problems mentioned above. It will present a methodology and examples of use of an automated tool that performs the analysis of a complete multiple-reflector system in an integrated multi-disciplinary environment (including CAD modeling, and structural and thermal analysis) at the click of a button. This tool, named MOD Tool (Millimeter-wave Optics Design Tool), has been designed and implemented as a distributed tool, with a client that runs almost identically on Unix, Mac, and Windows platforms, and a server that runs primarily on a Unix workstation and can interact with parallel supercomputers with simple instruction from the user interacting with the client.

  4. Multiple Lipid Nanoparticles (MLN), a New Generation of Lipid Nanoparticles for Drug Delivery Systems: Lamivudine-MLN Experimental Design.

    PubMed

    Cavalcanti, Suellen M T; Nunes, Cláudia; Lima, Sofia A C; Soares-Sobrinho, José L; Reis, Salette

    2017-06-01

    An optimized methodology for the development of a new generation of lipid nanoparticles, the multiple lipid nanoparticles (MLN) is described. MLN have characteristics between nanostructured lipid carriers (NLC) and multiple emulsions (W/O/W), but without the outer aqueous phase. The production is based on a hot homogenization method combined with high shear and ultrasonication. The antiretroviral agent lamivudine (3TC), was loaded in the MLN. For comparison purposes, NLC-3TC formulation was also developed and physico-chemically characterized by the same parameters as MLN-3TC. The development and optimization of MLN and NLC formulations were supported by a Quality by Design (QbD) approach. The MLN-3TC formulation exhibited a size of about 450 nm, polydispersity <0.3 and negative zeta potential > -20 mV. Furthermore, the morphology assessed by TEM showed a structure with multiples aqueous vacuoles. MLN-3TC was physically stable for at least 45 days, had low cytotoxicity and drug release studies showed a sustained and controlled release of 3TC under gastric and plasma-simulated conditions (at pH 7.4 for about 45 h). The optimized formulations present suitable profiles for oral administration. Overall, the results reveal that MLN present higher loading capacity and storage stability than NLC.

  5. Modeling and design of multiple buried junctions detectors for color systems development

    NASA Astrophysics Data System (ADS)

    Alexandre, Annick; Sou, Gerard; Ben Chouikha, Mohamed; Sedjil, Mohamed; Lu, Guo N.; Alquie, George

    2000-04-01

    Two novel integrated optical detectors called BDJ detector and BTJ detector have been developed in our laboratory. These two detectors have different applications: the BDJ detector elaborated in CMOS process can be used for wavelength or light flux detection while the BTJ detector based on a bipolar structure gives the trichromatics components of a light. To develop microsystems, we need simulation tools as SPICE model. So, we have elaborated a physical mode, proposed a parameters extraction method and study influence of different parameters for BDJ detectors. Simulations and measurements have validated these models. More, we prose a design of BTJ detectors for developing new color imaging systems.

  6. Check-Standard Testing Across Multiple Transonic Wind Tunnels with the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    Deloach, Richard

    2012-01-01

    This paper reports the result of an analysis of wind tunnel data acquired in support of the Facility Analysis Verification & Operational Reliability (FAVOR) project. The analysis uses methods referred to collectively at Langley Research Center as the Modern Design of Experiments (MDOE). These methods quantify the total variance in a sample of wind tunnel data and partition it into explained and unexplained components. The unexplained component is further partitioned in random and systematic components. This analysis was performed on data acquired in similar wind tunnel tests executed in four different U.S. transonic facilities. The measurement environment of each facility was quantified and compared.

  7. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Interplanetary Mission Design Using Chemical Propulsion

    NASA Technical Reports Server (NTRS)

    Englander, Jacob; Vavrina, Matthew

    2015-01-01

    The customer (scientist or project manager) most often does not want just one point solution to the mission design problem Instead, an exploration of a multi-objective trade space is required. For a typical main-belt asteroid mission the customer might wish to see the trade-space of: Launch date vs. Flight time vs. Deliverable mass, while varying the destination asteroid, planetary flybys, launch year, etcetera. To address this question we use a multi-objective discrete outer-loop which defines many single objective real-valued inner-loop problems.

  8. Development of an Ultra-Wideband Circularly Polarized Multiple Layer Dielectric Rod Antenna Design

    NASA Astrophysics Data System (ADS)

    Wainwright, Gregory D.

    This dissertations focuses on the development of a novel Ultra-Wideband (UWB) circularly polarized dielectric rod antenna (CPDRA) which yields a constant gain, pattern, and phase center. These properties are important in many applications. Within radar systems a constant phase center is desirable to avoid errors within downrange and crossrange measurements. In a reflector antenna the illumination, spillover, and phase efficiencies will remain the same over an ultra-wideband. Lastly, near field probes require smooth amplitude and phase patterns over frequency to avoid errors during the calibration process of the antenna under test. In this dissertation a novel CP feeding network has been developed for an ultra-wideband dielectric rod antenna. Circularly-polarized antennas have a major advantage over its linearly-polarized counterpart in that the polarization mismatch loss caused by misalignment between the polarizations of the incident fields and antenna can be avoided. This is important in satellite communications and broadcasts where signal propagation through the ionosphere can experience Faraday Rotation. A circularly polarized antenna is also helpful in mobile radar and communication systems where the receiving antennas orientation is not fixed. Previous research on UWB dielectric rod antenna designs has focused on Dual linear feeds. Each polarization within the dual linear feed is excited by a pair of linear launcher arms fed with a 0°-180° hybrid balun. The proposed CPDRA design does not require the 0°-180° hybrid baluns or 0°-90° hybrid for achieving CP operation. These hybrids will increase the antennas size, weight, cost, and reduce operational bandwidth. A design technique has been developed for an UWB multilayer dielectric waveguide used in a CPDRA antenna. This design technique uses near-field Electric field data from inside the waveguide, in conjunction with a genetic algorithm optimization to yield a wideband waveguide with a near field

  9. Multiple tail models including inverse measures for structural design under uncertainties

    NASA Astrophysics Data System (ADS)

    Ramu, Palaniappan

    Sampling-based reliability estimation with expensive computer models may be computationally prohibitive due to a large number of required simulations. One way to alleviate the computational expense is to extrapolate reliability estimates from observed levels to unobserved levels. Classical tail modeling techniques provide a class of models to enable this extrapolation using asymptotic theory by approximating the tail region of the cumulative distribution function (CDF). This work proposes three alternate tail extrapolation techniques including inverse measures that can complement classical tail modeling. The proposed approach, multiple tail models, applies the two classical and three alternate extrapolation techniques simultaneously to estimate inverse measures at the extrapolation regions and use the median as the best estimate. It is observed that the range of the five estimates can be used as a good approximation of the error associated with the median estimate. Accuracy and computational efficiency are competing factors in selecting sample size. Yet, as our numerical studies reveal, the accuracy lost to the reduction of computational power is very small in the proposed method. The method is demonstrated on standard statistical distributions and complex engineering examples.

  10. QuickProbs--a fast multiple sequence alignment algorithm designed for graphics processors.

    PubMed

    Gudyś, Adam; Deorowicz, Sebastian

    2014-01-01

    Multiple sequence alignment is a crucial task in a number of biological analyses like secondary structure prediction, domain searching, phylogeny, etc. MSAProbs is currently the most accurate alignment algorithm, but its effectiveness is obtained at the expense of computational time. In the paper we present QuickProbs, the variant of MSAProbs customised for graphics processors. We selected the two most time consuming stages of MSAProbs to be redesigned for GPU execution: the posterior matrices calculation and the consistency transformation. Experiments on three popular benchmarks (BAliBASE, PREFAB, OXBench-X) on quad-core PC equipped with high-end graphics card show QuickProbs to be 5.7 to 9.7 times faster than original CPU-parallel MSAProbs. Additional tests performed on several protein families from Pfam database give overall speed-up of 6.7. Compared to other algorithms like MAFFT, MUSCLE, or ClustalW, QuickProbs proved to be much more accurate at similar speed. Additionally we introduce a tuned variant of QuickProbs which is significantly more accurate on sets of distantly related sequences than MSAProbs without exceeding its computation time. The GPU part of QuickProbs was implemented in OpenCL, thus the package is suitable for graphics processors produced by all major vendors.

  11. QuickProbs—A Fast Multiple Sequence Alignment Algorithm Designed for Graphics Processors

    PubMed Central

    Gudyś, Adam; Deorowicz, Sebastian

    2014-01-01

    Multiple sequence alignment is a crucial task in a number of biological analyses like secondary structure prediction, domain searching, phylogeny, etc. MSAProbs is currently the most accurate alignment algorithm, but its effectiveness is obtained at the expense of computational time. In the paper we present QuickProbs, the variant of MSAProbs customised for graphics processors. We selected the two most time consuming stages of MSAProbs to be redesigned for GPU execution: the posterior matrices calculation and the consistency transformation. Experiments on three popular benchmarks (BAliBASE, PREFAB, OXBench-X) on quad-core PC equipped with high-end graphics card show QuickProbs to be 5.7 to 9.7 times faster than original CPU-parallel MSAProbs. Additional tests performed on several protein families from Pfam database give overall speed-up of 6.7. Compared to other algorithms like MAFFT, MUSCLE, or ClustalW, QuickProbs proved to be much more accurate at similar speed. Additionally we introduce a tuned variant of QuickProbs which is significantly more accurate on sets of distantly related sequences than MSAProbs without exceeding its computation time. The GPU part of QuickProbs was implemented in OpenCL, thus the package is suitable for graphics processors produced by all major vendors. PMID:24586435

  12. Trial of trazodone for posttraumatic stress disorder using a multiple baseline group design.

    PubMed

    Hertzberg, M A; Feldman, M E; Beckham, J C; Davidson, J R

    1996-08-01

    Six patients with combat-related posttraumatic stress disorder (PTSD) entered a multiple-baseline trial of trazodone, beginning with 50 mg/day and increasing to 400 mg/day until response was maximal. Total Clinician-Administered PTSD Scale scores decreased from a mean of 92 at baseline to 79 at end point, and self-reported PTSD symptoms as measured by the Davidson Trauma Scale paralleled these results (mean of 102 at baseline to 88 at end point). Based on clinician global improvement scores, four patients were rated as much improved and two were rated to be minimally improved. Improvement in social and occupational functioning, and depression was minimal. Available follow-up scores for PTSD symptoms indicated that gains were maintained. Sleep was the first symptom to improve at 2 to 3 months. No dropouts during the treatment period occurred, and reported side effects were quite low. These preliminary data suggest that trazodone may be effective in reducing the three primary clusters of symptoms of PTSD. These findings should be confirmed by using a larger sample in a double-blind, placebo-controlled study.

  13. Large-scale design of robust genetic circuits with multiple inputs and outputs for mammalian cells.

    PubMed

    Weinberg, Benjamin H; Pham, N T Hang; Caraballo, Leidy D; Lozanoski, Thomas; Engel, Adrien; Bhatia, Swapnil; Wong, Wilson W

    2017-05-01

    Engineered genetic circuits for mammalian cells often require extensive fine-tuning to perform as intended. We present a robust, general, scalable system, called 'Boolean logic and arithmetic through DNA excision' (BLADE), to engineer genetic circuits with multiple inputs and outputs in mammalian cells with minimal optimization. The reliability of BLADE arises from its reliance on recombinases under the control of a single promoter, which integrates circuit signals on a single transcriptional layer. We used BLADE to build 113 circuits in human embryonic kidney and Jurkat T cells and devised a quantitative, vector-proximity metric to evaluate their performance. Of 113 circuits analyzed, 109 functioned (96.5%) as intended without optimization. The circuits, which are available through Addgene, include a 3-input, two-output full adder; a 6-input, one-output Boolean logic look-up table; circuits with small-molecule-inducible control; and circuits that incorporate CRISPR-Cas9 to regulate endogenous genes. BLADE enables execution of sophisticated cellular computation in mammalian cells, with applications in cell and tissue engineering.

  14. Saccharomyces cerevisiae single-copy plasmids for auxotrophy compensation, multiple marker selection, and for designing metabolically cooperating communities

    PubMed Central

    Matsarskaia, Olga; Eckerstorfer, Florian; Ralser, Markus

    2016-01-01

    Auxotrophic markers are useful tools in cloning and genome editing, enable a large spectrum of genetic techniques, as well as facilitate the study of metabolite exchange interactions in microbial communities. If unused background auxotrophies are left uncomplemented however, yeast cells need to be grown in nutrient supplemented or rich growth media compositions, which precludes the analysis of biosynthetic metabolism, and which leads to a profound impact on physiology and gene expression. Here we present a series of 23 centromeric plasmids designed to restore prototrophy in typical Saccharomyces cerevisiae laboratory strains. The 23 single-copy plasmids complement for deficiencies in HIS3, LEU2, URA3, MET17 or LYS2 genes and in their combinations, to match the auxotrophic background of the popular functional-genomic yeast libraries that are based on the S288c strain. The plasmids are further suitable for designing self-establishing metabolically cooperating (SeMeCo) communities, and possess a uniform multiple cloning site to exploit multiple parallel selection markers in protein expression experiments. PMID:27830062

  15. Study on electrode design of PDP-like X-ray detector for enhancement of charge multiplication

    NASA Astrophysics Data System (ADS)

    Eom, Sangheum; Kim, Jongseok; Kang, Jungwon; Lee, Hakjae; Lee, Kisung

    2015-06-01

    In this article, a two-dimensional detector based on plasma display technology was investigated as a candidate for a flat-panel radiation detector. By using the three-dimensional Garfield code, the dependence of the electric field and multiplication on various electrode structures was examined. Based on the calculation of multiplication, three different electrode designs, including CAC, ridged CAC, and double-ridged CAC structures were selected and prototype detectors adopting these designs were fabricated and tested. The performance of these detectors was evaluated by measuring the charge density and sensitivity. The charge density of the double-ridged CAC detector during the X-ray for the on condition varied from 0.482 up to 2.59 μC /cm2 at the address bias scope of -500-1500 V, while the cathode voltage was locked at - 400 V. The sensitivity of the same detector was 0.596 nC / mR ṡcm2 in an electric field of 0.54 V/μm, which was the highest value. This was about one-third lower than the sensitivity of the amorphous selenium (a-Se) based detector at 10 V/μm.

  16. Design of artificial genetic regulatory networks with multiple delayed adaptive responses*

    NASA Astrophysics Data System (ADS)

    Kaluza, Pablo; Inoue, Masayo

    2016-06-01

    Genetic regulatory networks with adaptive responses are widely studied in biology. Usually, models consisting only of a few nodes have been considered. They present one input receptor for activation and one output node where the adaptive response is computed. In this work, we design genetic regulatory networks with many receptors and many output nodes able to produce delayed adaptive responses. This design is performed by using an evolutionary algorithm of mutations and selections that minimizes an error function defined by the adaptive response in signal shapes. We present several examples of network constructions with a predefined required set of adaptive delayed responses. We show that an output node can have different kinds of responses as a function of the activated receptor. Additionally, complex network structures are presented since processing nodes can be involved in several input-output pathways. Supplementary material in the form of one nets file available from the Journal web page at http://dx.doi.org/10.1140/epjb/e2016-70172-9

  17. Accelerated multidimensional radiofrequency pulse design for parallel transmission using concurrent computation on multiple graphics processing units.

    PubMed

    Deng, Weiran; Yang, Cungeng; Stenger, V Andrew

    2011-02-01

    Multidimensional radiofrequency (RF) pulses are of current interest because of their promise for improving high-field imaging and for optimizing parallel transmission methods. One major drawback is that the computation time of numerically designed multidimensional RF pulses increases rapidly with their resolution and number of transmitters. This is critical because the construction of multidimensional RF pulses often needs to be in real time. The use of graphics processing units for computations is a recent approach for accelerating image reconstruction applications. We propose the use of graphics processing units for the design of multidimensional RF pulses including the utilization of parallel transmitters. Using a desktop computer with four NVIDIA Tesla C1060 computing processors, we found acceleration factors on the order of 20 for standard eight-transmitter two-dimensional spiral RF pulses with a 64 × 64 excitation resolution and a 10-μsec dwell time. We also show that even greater acceleration factors can be achieved for more complex RF pulses. Copyright © 2010 Wiley-Liss, Inc.

  18. A methodology for the design of experiments in computational intelligence with multiple regression models.

    PubMed

    Fernandez-Lozano, Carlos; Gestal, Marcos; Munteanu, Cristian R; Dorado, Julian; Pazos, Alejandro

    2016-01-01

    The design of experiments and the validation of the results achieved with them are vital in any research study. This paper focuses on the use of different Machine Learning approaches for regression tasks in the field of Computational Intelligence and especially on a correct comparison between the different results provided for different methods, as those techniques are complex systems that require further study to be fully understood. A methodology commonly accepted in Computational intelligence is implemented in an R package called RRegrs. This package includes ten simple and complex regression models to carry out predictive modeling using Machine Learning and well-known regression algorithms. The framework for experimental design presented herein is evaluated and validated against RRegrs. Our results are different for three out of five state-of-the-art simple datasets and it can be stated that the selection of the best model according to our proposal is statistically significant and relevant. It is of relevance to use a statistical approach to indicate whether the differences are statistically significant using this kind of algorithms. Furthermore, our results with three real complex datasets report different best models than with the previously published methodology. Our final goal is to provide a complete methodology for the use of different steps in order to compare the results obtained in Computational Intelligence problems, as well as from other fields, such as for bioinformatics, cheminformatics, etc., given that our proposal is open and modifiable.

  19. Multiple Acoustical Matching Layer Design of Ultrasonic Transducer for Medical Application

    NASA Astrophysics Data System (ADS)

    Chen, Yeong-Chin; Wu, Sean

    2002-10-01

    Ultrasonic diagnostic equipment is widely used due to its merit of being a noninvasive technique as well as because it provides a clear real-time display of body tissue. Our focus is on the design of low-loss (high transmitting power) and wide-band transducers for ultrasonic diagnosis. The approach we have used consists of impedance matching the front face of the piezoelectric transducer to the propagating medium with a quarter wavelength impedance matching layer and inserting an unmatching quarter wavelength acoustical layer between the rear face and backing material. By tuning the acoustical impedance of the matching layer, transducers with wide-band characteristics and high transmitting power can be obtained. For the backing at the rear surface, a soft backing demonstrating a better impedance matching result which can improve the bandwidth, but exhibiting a longer duration impulse response should be used. A heavy backing would degrade the wide-band phenomena, but show a shorter time duration (<0.5 μS) for image application. To obtain the optimal solution to a specific design formulation, PSPICE (Personal Simulation Program with Integrated Circuit Emphasis) programming techniques can be applied. The PSPICE code of the Mason model is implemented to precisely predict the performance of the matched transducers such as impedance, insertion loss, bandwidth and duration of the impulse response. Good agreement between the simulation results and experimental results has been achieved.

  20. A methodology for the design of experiments in computational intelligence with multiple regression models

    PubMed Central

    Gestal, Marcos; Munteanu, Cristian R.; Dorado, Julian; Pazos, Alejandro

    2016-01-01

    The design of experiments and the validation of the results achieved with them are vital in any research study. This paper focuses on the use of different Machine Learning approaches for regression tasks in the field of Computational Intelligence and especially on a correct comparison between the different results provided for different methods, as those techniques are complex systems that require further study to be fully understood. A methodology commonly accepted in Computational intelligence is implemented in an R package called RRegrs. This package includes ten simple and complex regression models to carry out predictive modeling using Machine Learning and well-known regression algorithms. The framework for experimental design presented herein is evaluated and validated against RRegrs. Our results are different for three out of five state-of-the-art simple datasets and it can be stated that the selection of the best model according to our proposal is statistically significant and relevant. It is of relevance to use a statistical approach to indicate whether the differences are statistically significant using this kind of algorithms. Furthermore, our results with three real complex datasets report different best models than with the previously published methodology. Our final goal is to provide a complete methodology for the use of different steps in order to compare the results obtained in Computational Intelligence problems, as well as from other fields, such as for bioinformatics, cheminformatics, etc., given that our proposal is open and modifiable. PMID:27920952

  1. Multiple approaches to valuation of conservation design and low-impact development features in residential subdivisions.

    PubMed

    Bowman, Troy; Tyndall, John C; Thompson, Janette; Kliebenstein, James; Colletti, Joe P

    2012-08-15

    Residents, developers and civic officials are often faced with difficult decisions about appropriate land uses in and around metropolitan boundaries. Urban expansion brings with it the potential for negative environmental impacts, but there are alternatives, such as conservation subdivision design (CSD) or low-impact development (LID), which offer the possibility of mitigating some of these effects at the development site. Many urban planning jurisdictions across the Midwest do not currently have any examples of these designs and lack information to identify public support or barriers to use of these methods. This is a case study examining consumer value for conservation and low-impact design features in one housing market by using four different valuation techniques to estimate residents' willingness to pay for CSD and LID features in residential subdivisions. A contingent valuation survey of 1804 residents in Ames, IA assessed familiarity with and perceptions of subdivision development and used an ordered value approach to estimate willingness to pay for CSD and LID features. A majority of residents were not familiar with CSD or LID practices. Residents indicated a willingness to pay for most CSD and LID features with the exception of clustered housing. Gender, age, income, familiarity with LID practices, perceptions of attractiveness of features and the perceived effect of CSD and LID features on ease of future home sales were important factors influencing residents' willingness to pay. A hypothetical referendum measured willingness to pay for tax-funded conservation land purchases and estimated that a property tax of around $50 would be the maximum increase that would pass. Twenty-seven survey respondents participated in a subsequent series of experimental real estate negotiations that used an experimental auction mechanism to estimate willingness to pay for CSD and LID features. Participants indicated that clustered housing (with interspersed preserved forest

  2. Streamlining the design of promising clinical trials: in-vitro testing of antithrombotic regimens and multiple agonists of platelet activation.

    PubMed

    Schneider, David J; Sobel, Burton E

    2009-03-01

    Platelets are activated in vivo by multiple agonists; however, platelet function testing in vitro has been performed predominantly with only one or two agonists of platelet activation. Greater insight into anticipated effects of antithrombotic regimens should enhance the design of successful clinical trials. To test this concept, we assessed platelet activation induced by multiple agonists and two antithrombotic regimens, unfractionated heparin (UFH) and eptifibatide compared with bivalirudin and cangrelor. Blood samples from 10 patients with coronary artery disease were spiked with pharmacologic concentrations achieved in vivo of either UFH (1.2 U/ml) and eptifibatide (1.7 microg/ml), or with bivalirudin (8 microg/ml) and cangrelor (500 nmol/l). Platelet function was assessed with the use of flow cytometry. Agonists included thrombin (50 nmol/l), adenosine diphosphate (1 micromol/l), the collagen-mimetic convulxin (5 ng/ml), and platelet-activating factor (10 nmol/l). When platelet activation was identified by the surface expression of P-selectin in response to multiple agonists, the combination of bivalirudin and cangrelor suppressed activation more than UFH and eptifibatide. When platelet activation was identified by the activation of glycoprotein IIb-IIIa (PAC-1 binding), the combination of bivalirudin and cangrelor was more effective in suppressing activation in response to thrombin and adenosine diphosphate, whereas UFH and eptifibatide more effectively prevented binding of PAC-1 when platelets were activated with the collagen-mimetic convulxin. In conclusion, bivalirudin and cangrelor suppressed platelet activation in response to diverse agonists in vitro more than UFH and eptifibatide. These results and this approach to selection of promising interventions should be helpful in streamlining the design of clinical trials.

  3. Improving the efficiency of estimation in the additive hazards model for stratified case-cohort design with multiple diseases.

    PubMed

    Kim, Soyoung; Cai, Jianwen; Couper, David

    2016-01-30

    The case-cohort study design has often been used in studies of a rare disease or for a common disease with some biospecimens needing to be preserved for future studies. A case-cohort study design consists of a random sample, called the subcohort, and all or a portion of the subjects with the disease of interest. One advantage of the case-cohort design is that the same subcohort can be used for studying multiple diseases. Stratified random sampling is often used for the subcohort. Additive hazards models are often preferred in studies where the risk difference, instead of relative risk, is of main interest. Existing methods do not use the available covariate information fully. We propose a more efficient estimator by making full use of available covariate information for the additive hazards model with data from a stratified case-cohort design with rare (the traditional situation) and non-rare (the generalized situation) diseases. We propose an estimating equation approach with a new weight function. The proposed estimators are shown to be consistent and asymptotically normally distributed. Simulation studies show that the proposed method using all available information leads to efficiency gain and stratification of the subcohort improves efficiency when the strata are highly correlated with the covariates. Our proposed method is applied to data from the Atherosclerosis Risk in Communities study. Copyright © 2015 John Wiley & Sons, Ltd.

  4. Design a light pattern of multiple concentric circles for LED fishing lamps using Fourier series and an energy mapping method.

    PubMed

    Shen, S C; Li, J S; Huang, M C

    2014-06-02

    Fourier series and an energy mapping method were used in this study to design a lens that produces a light pattern of multiple concentric circles (LPMCC) for a light-emitting diode (LED) fishing lamp. Fourier series were used to represent the light intensity distribution curve (LIDC) of the LPMCC light pattern. Energy mapping involves performing angular energy mapping based on the LIDCs of an LED light source and LPMCC to design a freeform lens. Type I and Type II LPMCC lenses were designed according to the phototaxis behavior of fish to create a LPMCC light pattern of interleaving light-dark zones that attracts fish shoals to stay in an area for a long period. The experimental results indicated that, in comparing the LIDCs of the Type I and II lenses with the respective simulation values, the normalized cross-correlation (NCC) value reached 96%. According to a 24-hour observation of the phototaxis of Poecilia reticulata to evaluate the effectiveness of the proposed light pattern to attract fish, when a fish shoal was habituated to a light source that emitted constant illumination light, it gradually moved away from the intense light zone and hovered around the junction of the light and dark zones. In the future, the design used in this study can be applied to LED fishing lamps to replace traditional fishing lamps.

  5. Improving the efficiency of estimation in the additive hazards model for stratified case-cohort design with multiple diseases

    PubMed Central

    Kim, Soyoung; Cai, Jianwen; Couper, David

    2015-01-01

    The case-cohort study design has often been used in studies of a rare disease or for a common disease with some biospecimens needing to be preserved for future studies. A case-cohort study design consists of a random sample, called the subcohort, and all or a portion of the subjects with the disease of interest. One advantage of the case-cohort design is that the same subcohort can be used for studying multiple diseases. Stratified random sampling is often used for the subcohort. Additive hazards models are often preferred in studies where the risk difference, instead of relative risk, is of main interest. Existing methods do not use the available covariate information fully. We propose a more efficient estimator by making full use of available covariate information for the additive hazards model with data from a stratified case-cohort design with rare (the traditional situation) and non-rare (the generalized situation) diseases. We propose an estimating equation approach with a new weight function. The proposed estimators are shown to be consistent and asymptotically normally distributed. Simulation studies show that the proposed method using all available information leads to efficiency gain and stratification of the subcohort improves efficiency when the strata are highly correlated with the covariates. Our proposed method is applied to data from the Atherosclerosis Risk in Communities (ARIC) study. PMID:26310388

  6. Dependence of charge multiplication on different design parameters of LGAD devices

    NASA Astrophysics Data System (ADS)

    Jain, G.; Dalal, R.; Bhardwaj, A.; Ranjan, K.

    2017-03-01

    The Low Gain Avalanche Detectors (LGADs) have the unique characteristic to provide amplification to the particle signal by using a controlled local avalanche mechanism. These devices are being explored by the HEP community because, while it is known that in standard silicon detectors the signal-to-noise ratio falls drastically with fluence, in LGAD devices this can be made sufficiently high to potentially overcome this problem. However, the existing irradiation studies show that at high fluences, the LGAD internal gain disappears and is no more significant. In this work, we have studied the effect of various design parameters of the LGAD device on its gain characteristic, at different irradiation levels. With the acquired understanding, we have also tried to tune the LGAD gain so to be suited for operation in a high radiation environment.

  7. Design criteria for a multiple input land use system. [digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.; Bryant, N. A.

    1975-01-01

    A design is presented that proposes the use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remote sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set, and that images taken of thematic maps or from remote sensing platforms can be converted to a raster scan. A major advantage of the raster format is that x, y coordinates are implicitly recognized by their position in the scan, and z values can be treated as Boolean layers in a three-dimensional data space. Such a system permits the rapid incorporation of data sets, rapid comparison of data sets, and adaptation to variable scales by resampling the raster scans.

  8. Design criteria for a multiple input land use system. [digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.; Bryant, N. A.

    1975-01-01

    A design is presented that proposes the use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remote sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set, and that images taken of thematic maps or from remote sensing platforms can be converted to a raster scan. A major advantage of the raster format is that x, y coordinates are implicitly recognized by their position in the scan, and z values can be treated as Boolean layers in a three-dimensional data space. Such a system permits the rapid incorporation of data sets, rapid comparison of data sets, and adaptation to variable scales by resampling the raster scans.

  9. Electrical engineering and nontechnical design variables of multiple inductive loop systems for auditoriums.

    PubMed

    Alterovitz, Gil

    2004-01-01

    This research analyzed both engineering and nontechnical issues involved in the use of Induction Loop Amplification (ILA) devices in auditoriums or large gathering places for hard-of-hearing individuals. A variety of parameters need to be taken into account to determine an optimal shape/configuration for the ILA device. In many cases, an optimal configuration is different from those proposed for classroom use (Ross, 1969; Hodgson, 1986; Clevenger, 1992). Experimental results were obtained for a double-loop configuration in such a setting (a university gymnasium/auditorium in this case). The results demonstrate that a double-loop configuration is a viable possibility for auditorium use. Several variables using this configuration were examined, and experimentation was done. Various implications, including consequent nontechnical issues specific to this application, are discussed as well. Technical and nontechnical aspects of the ILA configuration need to be examined together when designing an optimal system.

  10. Designing a sampling scheme to reveal correlations between weeds and soil properties at multiple spatial scales.

    PubMed

    Metcalfe, H; Milne, A E; Webster, R; Lark, R M; Murdoch, A J; Storkey, J

    2016-02-01

    Weeds tend to aggregate in patches within fields, and there is evidence that this is partly owing to variation in soil properties. Because the processes driving soil heterogeneity operate at various scales, the strength of the relations between soil properties and weed density would also be expected to be scale-dependent. Quantifying these effects of scale on weed patch dynamics is essential to guide the design of discrete sampling protocols for mapping weed distribution. We developed a general method that uses novel within-field nested sampling and residual maximum-likelihood (reml) estimation to explore scale-dependent relations between weeds and soil properties. We validated the method using a case study of Alopecurus myosuroides in winter wheat. Using reml, we partitioned the variance and covariance into scale-specific components and estimated the correlations between the weed counts and soil properties at each scale. We used variograms to quantify the spatial structure in the data and to map variables by kriging. Our methodology successfully captured the effect of scale on a number of edaphic drivers of weed patchiness. The overall Pearson correlations between A. myosuroides and soil organic matter and clay content were weak and masked the stronger correlations at >50 m. Knowing how the variance was partitioned across the spatial scales, we optimised the sampling design to focus sampling effort at those scales that contributed most to the total variance. The methods have the potential to guide patch spraying of weeds by identifying areas of the field that are vulnerable to weed establishment.

  11. Decision analysis for designing marine protected areas for multiple species with uncertain fishery status.

    PubMed

    White, J Wilson; Botsford, Louis W; Moffitt, Elizabeth A; Fischer, Douglas T

    2010-09-01

    Marine protected areas (MPAs) are growing in popularity as a conservation tool, and there are increasing calls for additional MPAs. Meta-analyses indicate that most MPAs successfully meet the minimal goal of increasing biomass inside the MPA, while some do not, leaving open the important question of what makes MPAs successful. An often-overlooked aspect of this problem is that the success of fishery management outside MPA boundaries (i.e., whether a population is overfished) affects how well MPAs meet both conservation goals (e.g., increased biomass) and economic goals (e.g., minimal negative effects on fishery yield). Using a simple example of a system with homogeneous habitat and periodically spaced MPAs, we show that, as area in MPAs increases, (1) conservation value (biomass) may initially be zero, implying no benefit, then at some point increases monotonically; and (2) fishery yield may be zero, then increases monotonically to a maximum beyond which further increase in MPA area causes yield to decline. Importantly, the points at which these changes in slope occur vary among species and depend on management outside MPAs. Decision makers considering the effects of a potential system of MPAs on multiple species are confronted by a number of such cost-benefit curves, and it is usually impossible to maximize benefits and minimize costs for all species. Moreover, the precise shape of each curve is unknown due to uncertainty regarding the fishery status of each species. Here we describe a decision-analytic approach that incorporates existing information on fishery stock status to present decision makers with the range of likely outcomes of MPA implementation. To summarize results from many species whose overfishing status is uncertain, our decision-analysis approach involves weighted averages over both overfishing uncertainty and species. In an example from an MPA decision process in California, USA, an optimistic projection of future fishery management success led

  12. Design and evaluation of multiple level data staging for Blue Gene systems.

    SciTech Connect

    Isaila, F.; Blas, J. G.; Carretero, J.; Latham, R.; Ross, R.

    2011-06-01

    Parallel applications currently suffer from a significant imbalance between computational power and available I/O bandwidth. Additionally, the hierarchical organization of current Petascale systems contributes to an increase of the I/O subsystem latency. In these hierarchies, file access involves pipelining data through several networks with incremental latencies and higher probability of congestion. Future Exascale systems are likely to share this trait. This paper presents a scalable parallel I/O software system designed to transparently hide the latency of file system accesses to applications on these platforms. Our solution takes advantage of the hierarchy of networks involved in file accesses, to maximize the degree of overlap between computation, file I/O-related communication, and file system access. We describe and evaluate a two-level hierarchy for Blue Gene systems consisting of client-side and I/O node-side caching. Our file cache management modules coordinate the data staging between application and storage through the Blue Gene networks. The experimental results demonstrate that our architecture achieves significant performance improvements through a high degree of overlap between computation, communication, and file I/O.

  13. New Design for Rapid Prototyping of Digital Master Casts for Multiple Dental Implant Restorations

    PubMed Central

    Romero, Luis; Jiménez, Mariano; Espinosa, María del Mar; Domínguez, Manuel

    2015-01-01

    Aim This study proposes the replacement of all the physical devices used in the manufacturing of conventional prostheses through the use of digital tools, such as 3D scanners, CAD design software, 3D implants files, rapid prototyping machines or reverse engineering software, in order to develop laboratory work models from which to finish coatings for dental prostheses. Different types of dental prosthetic structures are used, which were adjusted by a non-rotatory threaded fixing system. Method From a digital process, the relative positions of dental implants, soft tissue and adjacent teeth of edentulous or partially edentulous patients has been captured, and a maser working model which accurately replicates data relating to the patients oral cavity has been through treatment of three-dimensional digital data. Results Compared with the conventional master cast, the results show a significant cost savings in attachments, as well as an increase in the quality of reproduction and accuracy of the master cast, with the consequent reduction in the number of patient consultation visits. The combination of software and hardware three-dimensional tools allows the optimization of the planning of dental implant-supported rehabilitations protocol, improving the predictability of clinical treatments and the production cost savings of master casts for restorations upon implants. PMID:26696528

  14. Design optimization of a fuzzy distributed generation (DG) system with multiple renewable energy sources

    NASA Astrophysics Data System (ADS)

    Ganesan, T.; Elamvazuthi, I.; Shaari, Ku Zilati Ku; Vasant, P.

    2012-09-01

    The global rise in energy demands brings major obstacles to many energy organizations in providing adequate energy supply. Hence, many techniques to generate cost effective, reliable and environmentally friendly alternative energy source are being explored. One such method is the integration of photovoltaic cells, wind turbine generators and fuel-based generators, included with storage batteries. This sort of power systems are known as distributed generation (DG) power system. However, the application of DG power systems raise certain issues such as cost effectiveness, environmental impact and reliability. The modelling as well as the optimization of this DG power system was successfully performed in the previous work using Particle Swarm Optimization (PSO). The central idea of that work was to minimize cost, minimize emissions and maximize reliability (multi-objective (MO) setting) with respect to the power balance and design requirements. In this work, we introduce a fuzzy model that takes into account the uncertain nature of certain variables in the DG system which are dependent on the weather conditions (such as; the insolation and wind speed profiles). The MO optimization in a fuzzy environment was performed by applying the Hopfield Recurrent Neural Network (HNN). Analysis on the optimized results was then carried out.

  15. New Design for Rapid Prototyping of Digital Master Casts for Multiple Dental Implant Restorations.

    PubMed

    Romero, Luis; Jiménez, Mariano; Espinosa, María Del Mar; Domínguez, Manuel

    2015-01-01

    This study proposes the replacement of all the physical devices used in the manufacturing of conventional prostheses through the use of digital tools, such as 3D scanners, CAD design software, 3D implants files, rapid prototyping machines or reverse engineering software, in order to develop laboratory work models from which to finish coatings for dental prostheses. Different types of dental prosthetic structures are used, which were adjusted by a non-rotatory threaded fixing system. From a digital process, the relative positions of dental implants, soft tissue and adjacent teeth of edentulous or partially edentulous patients has been captured, and a maser working model which accurately replicates data relating to the patients oral cavity has been through treatment of three-dimensional digital data. Compared with the conventional master cast, the results show a significant cost savings in attachments, as well as an increase in the quality of reproduction and accuracy of the master cast, with the consequent reduction in the number of patient consultation visits. The combination of software and hardware three-dimensional tools allows the optimization of the planning of dental implant-supported rehabilitations protocol, improving the predictability of clinical treatments and the production cost savings of master casts for restorations upon implants.

  16. Oligonucleotides designed to inhibit TLR9 block Herpes simplex virus type 1 infection at multiple steps.

    PubMed

    Sauter, Monica M; Gauger, Joshua J L; Brandt, Curtis R

    2014-09-01

    Herpes simplex virus type 1 (HSV-1) is an important human pathogen which requires activation of nuclear factor-kappa B (NFκB) during its replication cycle. The persistent nature of HSV-1 infection, and the emergence of drug-resistant strains, highlights the importance of research to develop new antiviral agents. Toll-like receptors (TLRs) play a prominent role during the early antiviral response by recognizing viral nucleic acid and gene products, activating NFκB, and stimulating the production of inflammatory cytokines. We demonstrate a significant effect on HSV-1 replication in ARPE-19 and Vero cells when oligonucleotides designed to inhibit TLR9 are added 2h prior to infection. A greater than 90% reduction in the yield of infectious virus was achieved at oligonucleotide concentrations of 10-20 μM. TLR9 inhibitory oligonucleotides prevented expression of essential immediate early herpes gene products as determined by immunofluorescence microscopy and Western blotting. TLR9 oligonucleotides also interfered with viral attachment and entry. A TLR9 inhibitory oligonucleotide containing five adjacent guanosine residues (G-ODN) exhibited virucidal activity and inhibited HSV-1 replication when added post-infection. The antiviral effect of the TLR9 inhibitory oligonucleotides did not depend on the presence of TLR9 protein, suggesting a mechanism of inhibition that is not TLR9 specific. TLR9 inhibitory oligonucleotides also reduced NFκB activity in nuclear extracts. Studies using these TLR inhibitors in the context of viral infection should be interpreted with caution.

  17. Design and synthesis of an amphiphilic graft hydrogel having a hydrophobic domain formed by multiple interactions.

    PubMed

    Nitta, Kyohei; Kimoto, Atsushi; Watanabe, Junji

    2016-11-01

    A novel hydrogel having hydrophobic oligo segments and hydrophilic poly(acrylamidoglycolic acid) (PAGA) as pH responsive polymer segments was designed and synthesized to be used as a soft biomaterial. Poly(trimethylene carbonate) (PTMC) as the side chain, for which the degrees of polymerization were 9, 19, and 49, and the composition ratios were 1, 5, and 10mol%, was used as the oligo segment in the hydrogel. The swelling ratio of the hydrogel was investigated under various changes in conditions such as pH, temperature, and hydrogen bonding upon urea addition. Under pH2-11 conditions, the graft gel reversibly swelled and shrank due to the effect of PAGA main chain. The interior morphology and skin layer of the hydrogel was observed by a scanning electron microscope. The hydrogel composed of PAGA as the hydrophilic polymer backbone had a sponge-like structure, with a pore size of approximately 100μm. On the other hand, upon increasing the ratio of trimethylene carbonate (TMC) units in the hydrogel, the pores became smaller or disappeared. Moreover, thickness of the skin layer significantly increased with the swelling ratio depended on the incorporation ratios of the PTMC macromonomer. Molecular incorporation in the hydrogel was evaluated using a dye as a model drug molecule. These features would play an important role in drug loading. Increasing the ratio of TMC units favored the adsorption of the dye and activation of the incorporation behavior. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Towards the Design of Unexploitable Construction Mechanisms for Multiple-Tree Based P2P Streaming Systems

    NASA Astrophysics Data System (ADS)

    Brinkmeier, Michael; Fischer, Mathias; Grau, Sascha; Schaefer, Guenter

    In peer-to-peer based live streaming systems, a great number of participants have to cooperate to efficiently and reliably distribute a continuous flow of data. Each receiving peer in return provides its resources to the system. Since these systems operate in a completely distributed manner, it is of particular importance, to prevent malicious members from harvesting important topology information or influencing the streaming system to their needs. In this article, we analyze potential attack methods on multiple-tree-based P2P streaming systems, discuss important design decisions to constrain the impact of malicious behaviour, and we introduce the new concept of peer testaments. By analyzing existing systems, we show that so far only few attention has been given to the design of unexploitable construction mechanisms. Based on the identified design decisions, we propose a novel streaming system and evaluate it by exposing it to different types of internal attackers. Our results show that these attackers have to spend large effort to reach relevant positions in the streaming topology and that their bandwidth contribution far outnumbers the damage they achieve.

  19. Design and Room-Temperature Operation of GaAs/AlGaAs Multiple Quantum Well Nanowire Lasers.

    PubMed

    Saxena, Dhruv; Jiang, Nian; Yuan, Xiaoming; Mokkapati, Sudha; Guo, Yanan; Tan, Hark Hoe; Jagadish, Chennupati

    2016-08-10

    We present the design and room-temperature lasing characteristics of single nanowires containing coaxial GaAs/AlGaAs multiple quantum well (MQW) active regions. The TE01 mode, which has a doughnut-shaped intensity profile and is polarized predominantly in-plane to the MQWs, is predicted to lase in these nanowire heterostructures and is thus chosen for the cavity design. Through gain and loss calculations, we determine the nanowire dimensions required to minimize loss for the TE01 mode and determine the optimal thickness and number of QWs for minimizing the threshold sheet carrier density. In particular, we show that there is a limit to the minimum and maximum number of QWs that are required for room-temperature lasing. Based on our design, we grew nanowires of a suitable diameter containing eight uniform coaxial GaAs/AlGaAs MQWs. Lasing was observed at room temperature from optically pumped single nanowires and was verified to be from TE01 mode by polarization measurements. The GaAs MQW nanowire lasers have a threshold fluence that is a factor of 2 lower than that previously demonstrated for room-temperature GaAs nanowire lasers.

  20. Controller design for delay-independent stability of linear time-invariant vibration systems with multiple delays

    NASA Astrophysics Data System (ADS)

    Mahmoodi Nia, Payam; Sipahi, Rifat

    2013-07-01

    One of the critical parameters that can deteriorate the effectiveness of active vibration control (AVC) is the delay in sensors. Especially, in remote sensing where delays are large, and in high-speed applications with even small delays, instability can be inevitable. This paper presents algebraic approaches to design controllers in order to achieve stability regardless of the amount of delays for AVC applications modeled by linear time-invariant systems with "multiple" constant delays. The approaches are based on a nonconservative framework, and can identify the regions in the controller gain space where delay-independent stability (DIS) is achievable. With these controllers, we demonstrate via simulations that vibration suppression, within certain excitation frequency bands, can be improved or be as effective as those in AVC applications without delays.

  1. After Action Report:Idaho National Laboratory (INL) 2014 Multiple Facility Beyond Design Basis (BDBE) Evaluated Drill October 21, 2014

    SciTech Connect

    Barnes, V. Scott

    2014-12-01

    On October 21, 2014, Idaho National Laboratory (INL), in coordination with local jurisdictions, and Department of Energy (DOE) Idaho Operations Office (DOE ID) conducted an evaluated drill to demonstrate the ability to implement the requirements of DOE O 151.1C, “Comprehensive Emergency Management System” when responding to a beyond design basis event (BDBE) scenario as outlined in the Office of Health, Safety, and Security Operating Experience Level 1 letter (OE-1: 2013-01). The INL contractor, Battelle Energy Alliance, LLC (BEA), in coordination with CH2M-WG Idaho, LLC (CWI), and Idaho Treatment Group LLC (ITG), successfully demonstrated appropriate response measures to mitigate a BDBE event that would impact multiple facilities across the INL while protecting the health and safety of personnel, the environment, and property. Offsite response organizations participated to demonstrate appropriate response measures.

  2. A Collaboratively Designed Child Mental Health Service Model: Multiple Family Groups for Urban Children with Conduct Difficulties

    PubMed Central

    McKay, Mary McKernan; Gopalan, Geetha; Franco, Lydia; Assael, Kara Dean; Chacko, Anil; Jackson, Jerrold; Fuss, Ashley

    2011-01-01

    This paper presents preliminary outcomes associated with an experimental, longitudinal study of a Multiple Family Group (MFG) service delivery approach set within thirteen urban outpatient clinics serving children and their families living in inner-city, primarily African American and Latino communities. Specifically, this paper focuses on parent reports of child oppositional behavior and parenting stress over time. MFG is a flexible, protocol-driven approach designed to address the most common reason for referral to outpatient child mental health clinics, childhood behavioral difficulties. The MFG also aims to enhance family-level engagement and retention in ongoing care. Further, the service delivery model was collaboratively developed with intensive input from parents rearing children with conduct difficulties, parent advocates, community-based child mental health providers and services research staff in order to ultimately expand the number of effective service models that can be situated within “real world,” urban child mental health settings. PMID:22194642

  3. Magneto-optical disk drive technology using multiple fiber-coupled flying optical heads. Part I. System design and performance.

    PubMed

    Wilde, J P; Heanue, J F; Tselikov, A A; Hurst, J E

    2001-02-10

    A novel flying-optical-head data storage technology is described. It is based on a micro-optical recording head that contains a silicon micromachined torsional mirror for high-bandwidth track following. Multiple heads and disks are contained in a Winchester-style rotating disk drive. Single-mode optical fibers provide light delivery to and from the heads. Both polarization-maintaining and low-birefringence fiber systems have been implemented for magneto-optical (MO) recording. A fixed optics module containing a laser diode, MO detection optics, and a 1 x N fiber bundle switch has been developed as an integral part of this new recording architecture. A 5.25-in. (13.33-cm), half-height prototype drive design and its performance are presented.

  4. Evaluation of an intervention for apathy after traumatic brain injury: a multiple-baseline, single-case experimental design.

    PubMed

    Lane-Brown, Amanda; Tate, Robyn

    2010-01-01

    Apathy is diminished initiation, sustained activity, and concern about goal-directed behaviors. It occurs in between 46% and 71% of adults with traumatic brain injury and has widespread effects. Despite this, evidence for treatment of apathy is sparse, with no evidence for treatments aimed at sustaining activity toward goal-directed behavior. A multiple-baseline, single-case experimental design evaluated a novel treatment for apathy in a 32-year-old man with traumatic brain injury. This treatment incorporated motivational interviewing and external compensation to increase sustained activity toward cumulative goals. A specific treatment effect was demonstrated. Reliable Change Indices indicated a significant decrease in apathy that was maintained at 1-month follow-up. Treatment had a strong and specific effect on treated goal-directed activity and decreased apathy. The success of treatment was dependent on initiation as well as sustaining goal-directed activity.

  5. Mechanical design of multiple zone plates precision alignment apparatus for hard X-ray focusing in twenty-nanometer scale

    DOEpatents

    Shu, Deming; Liu, Jie; Gleber, Sophie C.; Vila-Comamala, Joan; Lai, Barry; Maser, Jorg M.; Roehrig, Christian; Wojcik, Michael J.; Vogt, Franz Stefan

    2017-04-04

    An enhanced mechanical design of multiple zone plates precision alignment apparatus for hard x-ray focusing in a twenty-nanometer scale is provided. The precision alignment apparatus includes a zone plate alignment base frame; a plurality of zone plates; and a plurality of zone plate holders, each said zone plate holder for mounting and aligning a respective zone plate for hard x-ray focusing. At least one respective positioning stage drives and positions each respective zone plate holder. Each respective positioning stage is mounted on the zone plate alignment base frame. A respective linkage component connects each respective positioning stage and the respective zone plate holder. The zone plate alignment base frame, each zone plate holder and each linkage component is formed of a selected material for providing thermal expansion stability and positioning stability for the precision alignment apparatus.

  6. Acoustic telemetry and network analysis reveal the space use of multiple reef predators and enhance marine protected area design

    PubMed Central

    Lea, James S. E.; Humphries, Nicolas E.; von Brandis, Rainer G.; Clarke, Christopher R.; Sims, David W.

    2016-01-01

    Marine protected areas (MPAs) are commonly employed to protect ecosystems from threats like overfishing. Ideally, MPA design should incorporate movement data from multiple target species to ensure sufficient habitat is protected. We used long-term acoustic telemetry and network analysis to determine the fine-scale space use of five shark and one turtle species at a remote atoll in the Seychelles, Indian Ocean, and evaluate the efficacy of a proposed MPA. Results revealed strong, species-specific habitat use in both sharks and turtles, with corresponding variation in MPA use. Defining the MPA's boundary from the edge of the reef flat at low tide instead of the beach at high tide (the current best in Seychelles) significantly increased the MPA's coverage of predator movements by an average of 34%. Informed by these results, the larger MPA was adopted by the Seychelles government, demonstrating how telemetry data can improve shark spatial conservation by affecting policy directly. PMID:27412274

  7. Acoustic telemetry and network analysis reveal the space use of multiple reef predators and enhance marine protected area design.

    PubMed

    Lea, James S E; Humphries, Nicolas E; von Brandis, Rainer G; Clarke, Christopher R; Sims, David W

    2016-07-13

    Marine protected areas (MPAs) are commonly employed to protect ecosystems from threats like overfishing. Ideally, MPA design should incorporate movement data from multiple target species to ensure sufficient habitat is protected. We used long-term acoustic telemetry and network analysis to determine the fine-scale space use of five shark and one turtle species at a remote atoll in the Seychelles, Indian Ocean, and evaluate the efficacy of a proposed MPA. Results revealed strong, species-specific habitat use in both sharks and turtles, with corresponding variation in MPA use. Defining the MPA's boundary from the edge of the reef flat at low tide instead of the beach at high tide (the current best in Seychelles) significantly increased the MPA's coverage of predator movements by an average of 34%. Informed by these results, the larger MPA was adopted by the Seychelles government, demonstrating how telemetry data can improve shark spatial conservation by affecting policy directly.

  8. Adaptive iterative design (AID): a novel approach for evaluating the interactive effects of multiple stressors on aquatic organisms.

    PubMed

    Glaholt, Stephen P; Chen, Celia Y; Demidenko, Eugene; Bugge, Deenie M; Folt, Carol L; Shaw, Joseph R

    2012-08-15

    The study of stressor interactions by eco-toxicologists using nonlinear response variables is limited by required amounts of a priori knowledge, complexity of experimental designs, the use of linear models, and the lack of use of optimal designs of nonlinear models to characterize complex interactions. Therefore, we developed AID, an adaptive-iterative design for eco-toxicologist to more accurately and efficiently examine complex multiple stressor interactions. AID incorporates the power of the general linear model and A-optimal criteria with an iterative process that: 1) minimizes the required amount of a priori knowledge, 2) simplifies the experimental design, and 3) quantifies both individual and interactive effects. Once a stable model is determined, the best fit model is identified and the direction and magnitude of stressors, individually and all combinations (including complex interactions) are quantified. To validate AID, we selected five commonly co-occurring components of polluted aquatic systems, three metal stressors (Cd, Zn, As) and two water chemistry parameters (pH, hardness) to be tested using standard acute toxicity tests in which Daphnia mortality is the (nonlinear) response variable. We found after the initial data input of experimental data, although literature values (e.g. EC-values) may also be used, and after only two iterations of AID, our dose response model was stable. The model ln(Cd)*ln(Zn) was determined the best predictor of Daphnia mortality response to the combined effects of Cd, Zn, As, pH, and hardness. This model was then used to accurately identify and quantify the strength of both greater- (e.g. As*Cd) and less-than additive interactions (e.g. Cd*Zn). Interestingly, our study found only binary interactions significant, not higher order interactions. We conclude that AID is more efficient and effective at assessing multiple stressor interactions than current methods. Other applications, including life-history endpoints commonly

  9. Multiple feedback loop design in the tryptophan regulatory network of Escherichia coli suggests a paradigm for robust regulation of processes in series

    PubMed Central

    Bhartiya, Sharad; Chaudhary, Nikhil; Venkatesh, K.V; Doyle, Francis J

    2005-01-01

    Biological networks have evolved through adaptation in uncertain environments. Of the different possible design paradigms, some may offer functional advantages over others. These designs can be quantified by the structure of the network resulting from molecular interactions and the parameter values. One may, therefore, like to identify the design motif present in the evolved network that makes it preferable over other alternatives. In this work, we focus on the regulatory networks characterized by serially arranged processes, which are regulated by multiple feedback loops. Specifically, we consider the tryptophan system present in Escherichia coli, which may be conceptualized as three processes in series, namely transcription, translation and tryptophan synthesis. The multiple feedback loop motif results from three distinct negative feedback loops, namely genetic repression, mRNA attenuation and enzyme inhibition. A framework is introduced to identify the key design components of this network responsible for its physiological performance. We demonstrate that the multiple feedback loop motif, as seen in the tryptophan system, enables robust performance to variations in system parameters while maintaining a rapid response to achieve homeostasis. Superior performance, if arising from a design principle, is intrinsic and, therefore, inherent to any similarly designed system, either natural or engineered. An experimental engineering implementation of the multiple feedback loop design on a two-tank system supports the generality of the robust attributes offered by the design. PMID:16849267

  10. Design Research on Mathematics Education: Investigating the Progress of Indonesian Fifth Grade Students' Learning on Multiplication of Fractions with Natural Numbers

    ERIC Educational Resources Information Center

    Shanty, Nenden Octavarulia; Hartono, Yusuf; Putri, Ratu Ilma Indra; de Haan, Dede

    2011-01-01

    This study aimed at investigating the progress of students' learning on multiplication fractions with natural numbers through the five activity levels based on Realistic Mathematics Education (RME) approach proposed by Streefland. Design research was chosen to achieve this research goal. In design research, the Hypothetical Learning Trajectory…

  11. [Effects of multiple-trough sampling design and algorithm on the estimation of population and individual pharmacokinetic parameters].

    PubMed

    Ling, Jing; Qian, Li-Xuan; Ding, Jun-Jie; Jiao, Zheng

    2014-05-01

    The purpose of this study is to investigate the effects of multiple-trough sampling design and nonlinear mixed effect modeling (NONMEM) algorithm on the estimation of population and individual pharmacokinetic parameters. Oxcarbazepine and tacrolimus were used as one-compartment and two-compartment model drugs, respectively. Seven sampling designs were investigated using various number of trough concentrations per individual ranging from 1-4. Monte Carlo simulations were performed to produce state-steady trough concentrations. One-compartment model was used to fit simulated data from oxcarbazepine and tacrolimus. The accuracy and precision of the estimated parameters were evaluated using the median prediction error (PE), the median absolute PE and boxplot. The results indicated that trough concentrations could yield reliable estimates of apparent clearance (CL/F). For oxcarbazepine, as the number of trough concentrations per subject increased, the accuracy and precision of CL/F, between-subject variability (BSV) of CL/F and residual variability (RUV) tended to be improved. For tacrolimus, however, although no improvement were observed in the accuracy of CL/F and BSV of CL/F, the PE distribution ranges were significantly narrowed and the RUV estimates were less bias and imprecise. In terms of algorithm, Monte Carlo importance sampling (IMP) and IMP assisted by mode a posteriori estimation (IMPMAP) were consistently better than other methods. Additionally, the sampling design had no significant effects on the individual parameter estimates, which were only depended on the interaction between BSV and RUV in various algorithms. Decreased in BSV and RUV levels can improve the accuracy and precision of the estimation for both population and individual pharmacokinetic parameter estimates.

  12. Tailored design of electrospun composite nanofibers with staged release of multiple angiogenic growth factors for chronic wound healing.

    PubMed

    Lai, Huan-Ju; Kuan, Chen-Hsiang; Wu, Hsi-Chin; Tsai, Jui-Che; Chen, Tim-Mo; Hsieh, Dar-Jen; Wang, Tzu-Wei

    2014-10-01

    The objective of this research study is to develop a collagen (Col) and hyaluronic acid (HA) inter-stacking nanofibrous skin equivalent substitute with the programmable release of multiple angiogenic growth factors (vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF) and endothelial growth factor (EGF)) either directly embedded in the nanofibers or encapsulated in the gelatin nanoparticles (GNs) by electrospinning technology. The delivery of EGF and bFGF in the early stage is expected to accelerate epithelialization and vasculature sprouting, while the release of PDGF and VEGF in the late stage is with the aim of inducing blood vessels maturation. The physiochemical characterizations indicate that the Col-HA-GN nanofibrous membrane possesses mechanical properties similar to human native skin. The design of a particle-in-fiber structure allows growth factors for slow controlled release up to 1month. Cultured on biodegradable Col-HA membrane with four kinds of growth factors (Col-HA w/4GF), endothelial cells not only increase in growth rate but also form a better network with a thread-like tubular structure. The therapeutic effect of Col-HA w/4GF membrane on streptozotocin (STZ)-induced diabetic rats reveals an accelerated wound closure rate, together with elevated collagen deposition and enhanced maturation of vessels, as revealed by Masson's trichrome stain and immunohistochemical analysis, respectively. From the above, the electrospun Col-HA-GN composite nanofibrous skin substitute with a stage-wise release pattern of multiple angiogenic factors could be a promising bioengineered construct for chronic wound healing in skin tissue regeneration.

  13. Design of nateglinide controlled release tablet containing erosion matrix tablet and multiple administration study in normal beagle dogs.

    PubMed

    Makino, Chisato; Sakai, Hidetoshi; Okano, Akira; Yabuki, Akira

    2009-09-01

    We designed a single unit type tablet formulation containing nateglinide to decrease both postprandial blood glucose level (PBG) and fasting blood glucose level (FBG) in normal beagle dogs. The tablet was a dry coated tablet comprising both a core tablet (an erosion matrix tablet: a controlled release portion(nateglinide: 90 mg)) and an outer shell (an immediate release portion (nateglinide: 60 mg)). The weight, the diameter and the hardness of the obtained tablet were 416.1 mg, 10 mmpsi, about 60 N, respectively. The dissolution study of the obtained tablet in pH 1.2 or 6.8 showed that the nateglinide in the immediate release portion dissolved in almost 30 min., and that 30 min after the dissolution test started, the nateglinide in the controlled release portion had dissolved slowly. An in vivo single oral administration study using normal beagle dogs showed the bioavailability value of the obtained nateglinide dry coated tablets against nateglinide immediate release tablets was 73.6%, although the value of nateglinide controlled release tablets containing enteric coated granules was 57.2-60.8%. An in vivo multiple oral administration study (b.i.d. (interval: 12 h), 8 d) using normal beagle dogs showed the reproducibility of nateglinide absorption. In addition, decreases in both PBG and FBG were observed. The ability to decrease the blood glucose level did not weaken during a multiple administration. On the basis of the above results, a controlled release formulation containing a short-acting type oral blood glucose regulator, not only nateglinide but meglitinides (repaglinide, mitiglinide, etc.) was suggested to enable control of both PBG and FBG for moderate and severe diabetes patients.

  14. Comparison of Multiple Linear Regressions and Neural Networks based QSAR models for the design of new antitubercular compounds.

    PubMed

    Ventura, Cristina; Latino, Diogo A R S; Martins, Filomena

    2013-01-01

    The performance of two QSAR methodologies, namely Multiple Linear Regressions (MLR) and Neural Networks (NN), towards the modeling and prediction of antitubercular activity was evaluated and compared. A data set of 173 potentially active compounds belonging to the hydrazide family and represented by 96 descriptors was analyzed. Models were built with Multiple Linear Regressions (MLR), single Feed-Forward Neural Networks (FFNNs), ensembles of FFNNs and Associative Neural Networks (AsNNs) using four different data sets and different types of descriptors. The predictive ability of the different techniques used were assessed and discussed on the basis of different validation criteria and results show in general a better performance of AsNNs in terms of learning ability and prediction of antitubercular behaviors when compared with all other methods. MLR have, however, the advantage of pinpointing the most relevant molecular characteristics responsible for the behavior of these compounds against Mycobacterium tuberculosis. The best results for the larger data set (94 compounds in training set and 18 in test set) were obtained with AsNNs using seven descriptors (R(2) of 0.874 and RMSE of 0.437 against R(2) of 0.845 and RMSE of 0.472 in MLRs, for test set). Counter-Propagation Neural Networks (CPNNs) were trained with the same data sets and descriptors. From the scrutiny of the weight levels in each CPNN and the information retrieved from MLRs, a rational design of potentially active compounds was attempted. Two new compounds were synthesized and tested against M. tuberculosis showing an activity close to that predicted by the majority of the models. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  15. Computer design, synthesis, and bioactivity analyses of drugs like fingolimod used in the treatment of multiple sclerosis.

    PubMed

    Turgut, Gurbet Çelik; Doyduk, Doğukan; Yıldırır, Yılmaz; Yavuz, Serkan; Akdemir, Atilla; Dişli, Ali; Şen, Alaattin

    2017-01-15

    Multiple sclerosis (MS) is a very common disease of vital importance. In the MS treatment, some drugs such as fingolimod which help to protect nerves from damage are used. The main goal of the drug therapy in MS is to take control of the inflammation which leads to the destruction of myelin and axons in nerve cell and thus prevent and stop the progression of the disease. Fingolimod (FTY720) is an orally active immunomodulatory drug that has been used for the treatment of relapsing-remitting multiple sclerosis. It is a sphingosine-1-phosphate receptor modulator which prevents lymphocytes from contributing to an autoimmune reaction by inhibiting egress of lymphocytes them from lymph nodes. In this study, we have computer designed, synthesized and characterized two novel derivatives of FTY720, F1-12h and F2-9, and have determined their underlying mechanism of their beneficial effect in SH-SY5Y, SK-N-SH, and U-118 MG cell lines. For this purpose, we first determined the regulation of the cAMP response element (CRE) activity and cAMP concentration by F1-12h and F2-9 together with FTY720 using pGL4.29 luciferase reporter assay and cAMP immunoassay, respectively. Then, we have determined their effect on MS- and GPCR-related gene expression profiles using custom arrays along with FTY720 treatment at non-toxic doses (EC10). It was found that both derivatives significantly activate CRE and increase cAMP concentration in all three cell lines, indicating that they activate cAMP pathway through cell surface receptors as FTY720 does. Furthermore, F1-12h and F2-9 modulate the expression of the pathway related genes that are important in inflammatory signaling, cAMP signaling pathway, cell migration as well as diverse receptor and transcription factors. Expression of the genes involved in myelination was also increased by the treatment with F1-12h and F2-9. In summary, our data demonstrate that the two novel FTY720 derivatives act as anti-inflammatory ultimately by influencing the

  16. Architecture and design to support rapid prototyping and multiple dynamic models for the Virtual SpacePlane project

    NASA Astrophysics Data System (ADS)

    Banks, Sheila B.; Stytz, Martin R.; Rothermel, Scott A.; Johnson, Troy D.

    1998-08-01

    and architectural framework for the user interface development. To achieve accurate and high fidelity performance for the VSP throughout its operational regime, the system integrates aerodynamics and astrodynamics models into a single seamless high fidelity model of the VSP's dynamics. In this paper we discuss the software architecture and design of the Virtual SpacePlane and describe how it supports the transition between motion models, the design of the dynamics software module, and techniques for employment of multiple dynamics models within a single virtual environment actor. We describe how we used rapid prototyping to refine requirements, improve the implementation, and accommodate new requirements throughout the project. We conclude the paper with a brief discussion of results and present suggestions for additional work.

  17. Incorporating 3D-printing technology in the design of head-caps and electrode drives for recording neurons in multiple brain regions.

    PubMed

    Headley, Drew B; DeLucca, Michael V; Haufler, Darrell; Paré, Denis

    2015-04-01

    Recent advances in recording and computing hardware have enabled laboratories to record the electrical activity of multiple brain regions simultaneously. Lagging behind these technical advances, however, are the methods needed to rapidly produce microdrives and head-caps that can flexibly accommodate different recording configurations. Indeed, most available designs target single or adjacent brain regions, and, if multiple sites are targeted, specially constructed head-caps are used. Here, we present a novel design style, for both microdrives and head-caps, which takes advantage of three-dimensional printing technology. This design facilitates targeting of multiple brain regions in various configurations. Moreover, the parts are easily fabricated in large quantities, with only minor hand-tooling and finishing required.

  18. Incorporating 3D-printing technology in the design of head-caps and electrode drives for recording neurons in multiple brain regions

    PubMed Central

    DeLucca, Michael V.; Haufler, Darrell; Paré, Denis

    2015-01-01

    Recent advances in recording and computing hardware have enabled laboratories to record the electrical activity of multiple brain regions simultaneously. Lagging behind these technical advances, however, are the methods needed to rapidly produce microdrives and head-caps that can flexibly accommodate different recording configurations. Indeed, most available designs target single or adjacent brain regions, and, if multiple sites are targeted, specially constructed head-caps are used. Here, we present a novel design style, for both microdrives and head-caps, which takes advantage of three-dimensional printing technology. This design facilitates targeting of multiple brain regions in various configurations. Moreover, the parts are easily fabricated in large quantities, with only minor hand-tooling and finishing required. PMID:25652930

  19. Evaluation of multiple hydraulic models in generating design/near-real time flood inundation extents under various geophysical settings

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Rajib, M. A.; Jafarzadegan, K.; Merwade, V.

    2015-12-01

    Application of land surface/hydrologic models within an operational flood forecasting system can provide probable time of occurrence and magnitude of streamflow at specific locations along a stream. Creating time-varying spatial extent of flood inundation and depth requires the use of a hydraulic or hydrodynamic model. Models differ in representing river geometry and surface roughness which can lead to different output depending on the particular model being used. The result from a single hydraulic model provides just one possible realization of the flood extent without capturing the uncertainty associated with the input or the model parameters. The objective of this study is to compare multiple hydraulic models toward generating ensemble flood inundation extents. Specifically, relative performances of four hydraulic models, including AutoRoute, HEC-RAS, HEC-RAS 2D, and LISFLOOD are evaluated under different geophysical conditions in several locations across the United States. By using streamflow output from the same hydrologic model (SWAT in this case), hydraulic simulations are conducted for three configurations: (i) hindcasting mode by using past observed weather data at daily time scale in which models are being calibrated against USGS streamflow observations, (ii) validation mode using near real-time weather data at sub-daily time scale, and (iii) design mode with extreme streamflow data having specific return periods. Model generated inundation maps for observed flood events both from hindcasting and validation modes are compared with remotely sensed images, whereas the design mode outcomes are compared with corresponding FEMA generated flood hazard maps. The comparisons presented here will give insights on probable model-specific nature of biases and their relative advantages/disadvantages as components of an operational flood forecasting system.

  20. Italian multicentre observational study of the prevalence of CCSVI in multiple sclerosis (CoSMo study): rationale, design, and methodology.

    PubMed

    Comi, Giancarlo; Battaglia, Mario Alberto; Bertolotto, Antonio; Del Sette, Massimo; Ghezzi, Angelo; Malferrari, Giovanni; Salvetti, Marco; Sormani, Maria Pia; Tesio, Luigi; Stolz, Erwin; Mancardi, Gianluigi

    2013-08-01

    Chronic cerebro-spinal venous insufficiency (CCSVI) has been proposed as a "congenital malformation" implicated in the pathogenesis of multiple sclerosis (MS). However, numerous studies failed to confirm its presence in MS patients. This paper presents the rationale, design, and methodology adopted in the CoSMo study, conducted with the aim of verifying whether or not CCSVI is linked to MS. The primary endpoint of the CoSMo study is to compare the prevalence of CCSVI in patients with MS versus patients affected by other neurodegenerative diseases (OND) and healthy volunteers. CoSMo is a multicenter, blinded, prevalence study recruiting 2,000 adult subjects, involving 43 MS centers across Italy. Assessment of the presence or absence of CCSVI is performed by color-coded duplex (CCD) sonography and two out of the five criteria according to Zamboni are necessary for the diagnosis of CCSVI. Local CCD examination carried out by a certified sonologist and the central image readings performed by experts in the field are blinded. An advanced protocol is also described in this paper. The application of a rigorous methodological design will definitively confirm whether an association exists between CCSVI and MS. Should an association be observed, this study also further examines the link between CCSVI and the severity of MS. The addition of subgroups without MS and OND also provides information on whether CCSVI is specific to MS only. Results from the CoSMo study will play a crucial role in the possible studies concerning the potential treatment of CCSVI in MS.

  1. Treatment of comorbid attention-deficit/hyperactivity disorder and anxiety in children: a multiple baseline design analysis.

    PubMed

    Jarrett, Matthew A; Ollendick, Thomas H

    2012-04-01

    The present study evaluated a 10-week psychosocial treatment designed specifically for children with attention-deficit/hyperactivity disorder (ADHD) and a comorbid anxiety disorder. Using a nonconcurrent multiple baseline design, the authors treated 8 children ages 8-12 with ADHD, combined type, and at least 1 of 3 major anxiety disorders (separation anxiety disorder, generalized anxiety disorder, social phobia). The integrated treatment protocol involved parent management training for ADHD and family-based cognitive-behavioral therapy for anxiety. Pretreatment assessments included semistructured diagnostic interviews and other standardized measures to determine study eligibility. Children were randomized to 1 of 3 baseline control conditions (i.e., 2, 3, or 4 weeks) and subsequently treated in a university-based psychosocial treatment clinic. Weekly assessments of ADHD and anxiety disorder symptoms occurred throughout treatment and comprehensive assessments were obtained at pretreatment, 1-week posttreatment, and 6-months posttreatment. Single-case results supported greater success in the treatment phase relative to the baseline phase for both ADHD and anxiety symptoms, and ADHD and anxiety symptoms appeared to change concurrently. Pre-post group analyses revealed significant and clinically meaningful improvements in ADHD and anxiety symptoms at 1-week posttreatment, but only anxiety symptoms moved into the subclinical range. At 6-months follow-up, treatment effects were maintained with new movement into the subclinical range for ADHD. The present study provides initial data on an integrated treatment protocol for ADHD and anxiety. Further replication and evaluation are needed. Implications of the findings are discussed. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  2. Optimum design of family structure and allocation of resources in association mapping with lines from multiple crosses

    PubMed Central

    Liu, W; Maurer, H P; Reif, J C; Melchinger, A E; Utz, H F; Tucker, M R; Ranc, N; Della Porta, G; Würschum, T

    2013-01-01

    Family mapping is based on multiple segregating families and is becoming increasingly popular because of its advantages over population mapping. Athough much progress has been made recently, the optimum design and allocation of resources for family mapping remains unclear. Here, we addressed these issues using a simulation study, resample model averaging and cross-validation approaches. Our results show that in family mapping, the predictive power and the accuracy of quatitative trait loci (QTL) detection depend greatly on the population size and phenotyping intensity. With small population sizes or few test environments, QTL results become unreliable and are hampered by a large bias in the estimation of the proportion of genotypic variance explained by the detected QTL. In addition, we observed that even though good results can be achieved with low marker densities, no plateau is reached with our full marker complement. This suggests that higher quality results could be achieved with greater marker densities or sequence data, which will be available in the near future for many species. PMID:23047199

  3. Compassion-Based Therapy for Trauma-Related Shame and Posttraumatic Stress: Initial Evaluation Using a Multiple Baseline Design.

    PubMed

    Au, Teresa M; Sauer-Zavala, Shannon; King, Matthew W; Petrocchi, Nicola; Barlow, David H; Litz, Brett T

    2017-03-01

    Accumulating research suggests that shame can strongly contribute to the development and maintenance of posttraumatic stress disorder (PTSD). Interventions that promote self-compassion have shown promise for reducing shame related to various clinical problems, but this approach has not been systematically evaluated for traumatized individuals. The aim of this study was to develop a brief compassion-based therapy and assess its efficacy for reducing trauma-related shame and PTSD symptoms. Using a multiple baseline experimental design, the intervention was evaluated in a community sample of trauma-exposed adults (N=10) with elevated trauma-related shame and PTSD symptoms. Participants completed weekly assessments during a 2-, 4-, or 6-week baseline phase and a 6-week treatment phase, and at 2 and 4weeks after the intervention. By the end of treatment, 9 of 10 participants demonstrated reliable decreases in PTSD symptom severity, while 8 of 10 participants showed reliable reductions in shame. These improvements were maintained at 2- and 4-week follow-up. The intervention was also associated with improvements in self-compassion and self-blame. Participants reported high levels of satisfaction with the intervention. Results suggest that the intervention may be useful as either a stand-alone treatment or as a supplement to other treatments. Copyright © 2016. Published by Elsevier Ltd.

  4. Initial evaluation of an integrated treatment for comorbid PTSD and smoking using a nonconcurrent, multiple-baseline design.

    PubMed

    Feldner, Matthew T; Smith, Rose C; Monson, Candice M; Zvolensky, Michael J

    2013-09-01

    The present study examined an integrated treatment for comorbid posttraumatic stress disorder (PTSD) and smoking entitled "Smoke-Free to Overcome PTSD: An Integrated Treatment" (STOP IT program). A nonconcurrent multiple-baseline design was used with six community-recruited adult smokers with PTSD to investigate both patient acceptance of the treatment and its initial efficacy on both PTSD and smoking. Potential order effects of exposure-based and affect management components were also examined. A gold-standard assessment strategy that included the Clinician Administered PTSD Scale (Blake et al., 1995) and biochemical verification of self-reported smoking status was employed to measure primary targets of treatment. Results suggested that the STOP IT program was well tolerated. There were clinically significant improvements in PTSD outcomes, but only temporary reductions in smoking. Participants' relatively low posttreatment smoking levels increased by the follow-up assessment, although not to baseline levels. Treatment component order did not appear to affect treatment outcomes, but those who were assigned to the exposure-focused writing prior to affect management training condition appeared more likely to discontinue treatment before beginning exposure. These preliminary data support the safety, acceptability, and potential efficacy of the STOP IT program. Future investigation of the STOP IT program should include testing the incremental efficacy of increasing the dose of smoking-focused intervention, as well as randomized controlled tests of the treatment that employ gold standards for treatment outcome research. Copyright © 2013. Published by Elsevier Ltd.

  5. Single-subject research in rehabilitation: a review of studies using AB, withdrawal, multiple baseline, and alternating treatments designs.

    PubMed

    Backman, C L; Harris, S R; Chisholm, J A; Monette, A D

    1997-10-01

    To review the "methodologic rules" for using single-subject research designs (SSRDs) and to review the use of SSRDs in rehabilitation research of the past decade. CINAHL and MEDLINE searches using "single subject" and "single system" as key words for the period 1985-1995 yielded 61 articles related to rehabilitation. Studies were selected for review if they described one of four commonly used SSRDs, specifically AB, withdrawal, multiple baseline, or alternating treatments. Studies cited were identified by consensus and either exemplify adherence to the experimental rules of SSRDs or illustrate errors that result in threats to the validity of stated findings. All four types of SSRDs have been reported in rehabilitation studies, sometimes incorrectly. SSRDs, with their client-centered focus, are ideally suited for researching human behavior in the rehabilitation practice environment. Although numerous sources clearly identify the methodologic requirements for single-subject experiments, several studies violate the basic rules, threatening the validity of the results of these studies. Other properly applied SSRDs illustrate the strengths of this approach, which can produce empirical support for rehabilitation interventions.

  6. A Monte Carlo evaluation of masked visual analysis in response-guided versus fixed-criteria multiple-baseline designs.

    PubMed

    Ferron, John M; Joo, Seang-Hwane; Levin, Joel R

    2017-09-09

    We developed masked visual analysis (MVA) as a structured complement to traditional visual analysis. The purpose of the present investigation was to compare the effects of computer-simulated MVA of a four-case multiple-baseline (MB) design in which the phase lengths are determined by an ongoing visual analysis (i.e., response-guided) versus those in which the phase lengths are established a priori (i.e., fixed criteria). We observed an acceptably low probability (less than .05) of false detection of treatment effects. The probability of correctly detecting a true effect frequently exceeded .80 and was higher when: (a) the masked visual analyst extended phases based on an ongoing visual analysis, (b) the effects were larger, (c) the effects were more immediate and abrupt, and (d) the effects of random and extraneous error factors were simpler. Our findings indicate that MVA is a valuable combined methodological and data-analysis tool for single-case intervention researchers. © 2017 Society for the Experimental Analysis of Behavior.

  7. Design and Performance of a Sensor System for Detection of Multiple Chemicals Using an External Cavity Quantum Cascade Laser

    SciTech Connect

    Phillips, Mark C.; Taubman, Matthew S.; Bernacki, Bruce E.; Cannon, Bret D.; Schiffern, John T.; Myers, Tanya L.

    2010-01-23

    We describe the performance of a sensor system designed for simultaneous detection of multiple chemicals with both broad and narrow absorption features. The sensor system consists of a broadly tunable external cavity quantum cascade laser (ECQCL), multi-pass Herriott cell, and custom low-noise electronics. The ECQCL features a rapid wavelength tuning rate of 2265 cm 1/s (15660 nm/s) over its tuning range of 1150-1270 cm 1 (7.87-8.70 μm), which permits detection of molecules with broad absorption features and dynamic concentrations, while the 0.2 cm-1 spectral resolution of the ECQCL system allows measurement of small molecules with atmospherically broadened absorption lines. High-speed amplitude modulation and low-noise electronics are used to improve the ECQCL performance for direct absorption measurements. We demonstrate simultaneous detection of Freon-134a (1,1,1,2-tetrafluoroethane), ammonia (NH3), and nitrous oxide (N2O) at low-ppb concentrations in field measurements of atmospheric chemical releases from a point source.

  8. Design of a biomass-to-biorefinery logistics system through bio-inspired metaheuristic optimization considering multiple types of feedstocks

    NASA Astrophysics Data System (ADS)

    Trueba, Isidoro

    fossil fuels to biofuels. In many ways biomass is a unique renewable resource. It can be stored and transported relatively easily in contrast to renewable options such as wind and solar, which create intermittent electrical power that requires immediate consumption and a connection to the grid. This thesis presents two different models for the design optimization of a biomass-to-biorefinery logistics system through bio-inspired metaheuristic optimization considering multiple types of feedstocks. This work compares the performance and solutions obtained by two types of metaheuristic approaches; genetic algorithm and ant colony optimization. Compared to rigorous mathematical optimization methods or iterative algorithms, metaheuristics do not guarantee that a global optimal solution can be found on some class of problems. Problems with similar characteristics to the one presented in this thesis have been previously solved using linear programming, integer programming and mixed integer programming methods. However, depending on the type of problem, these mathematical or complete methods might need exponential computation time in the worst-case. This often leads to computation times too high for practical purposes. Therefore, this thesis develops two types of metaheuristic approaches for the design optimization of a biomass-to-biorefinery logistics system considering multiple types of feedstocks and shows that metaheuristics are highly suitable to solve hard combinatorial optimization problems such as the one addressed in this research work.

  9. Promoting Generalized Social Interactions Using Puppets and Script Training in an Integrated Preschool: A Single-Case Study Using Multiple Baseline Design.

    ERIC Educational Resources Information Center

    Gronna, Sarah S.; Serna, Loretta A.; Kennedy, Craig H.; Prater, Mary Anne

    1999-01-01

    Puppet script training was used to teach the social skills of greeting, responding to conversations, and initiating conversations to a preschool child with visual impairments. A single-case study using a multiple-baseline design demonstrated that the intervention increased performance of social skills during recess with peers. (Author/MKA)

  10. An assistive device designed to convey independent donning of a shuttle lock trans-tibial prosthesis for a multiple limb amputee.

    PubMed

    Tamir, E; Heim, M; Oppenheim, U; Siev-Ner, I

    2003-04-01

    This contribution describes a simple device designed to convey independent donning of a shuttle lock trans-tibial prosthesis for a multiple limb amputee. The device is made of a post with a shuttle lock mechanism at one end and a plate covered by rubber at the other end. This device enables correct positioning of the silicone liner and independent attachment to the prosthesis.

  11. Hierarchical-genetic-algorithm-based design of a large scale Fresnel lens for a reading light system with multiple LED sources.

    PubMed

    Chen, Wen-Gong; Uang, Chii-Maw

    2006-10-20

    A conventional Fresnel lens is suitable to be used in the reading light system due to its features of directing and collecting light rays, as well as its properties of being essentially flat, plastic, lightweight, and cost efficient. However, it is not suitable for a reading light system with multiple light sources. To a reading light system with multiple light sources, a Fresnel lens with suitably designed groove angles can be used to improve the performance of that system in both illuminance and uniformity. Nevertheless, suitable groove angles are rather difficult to find if a Fresnel lens consists of a lot of groove angles and each angle covers a wide range of degrees. We develop a hierarchical genetic algorithm (HGA) to search for a set of optimal groove angles to design a Fresnel lens for a reading light system with multiple light sources from an enormous searching space. In addition, the groove angles of the Fresnel lens are directly derived from a conventional Fresnel lens database. The design goal is to maximize the illuminance and simultaneously maintain the uniformity of light rays incident to a specified reading surface. As a result, we can demonstrate that a HGA really works better than a genetic algorithm and the optimally designed Fresnel lens, indeed, offers a better light-guiding performance than a conventional Fresnel lens for a multiple-LED reading light system.

  12. Promoting Generalized Social Interactions Using Puppets and Script Training in an Integrated Preschool: A Single-Case Study Using Multiple Baseline Design.

    ERIC Educational Resources Information Center

    Gronna, Sarah S.; Serna, Loretta A.; Kennedy, Craig H.; Prater, Mary Anne

    1999-01-01

    Puppet script training was used to teach the social skills of greeting, responding to conversations, and initiating conversations to a preschool child with visual impairments. A single-case study using a multiple-baseline design demonstrated that the intervention increased performance of social skills during recess with peers. (Author/MKA)

  13. Vitalum study design: RCT evaluating the efficacy of tailored print communication and telephone motivational interviewing on multiple health behaviors

    PubMed Central

    van Keulen, Hilde M; Mesters, Ilse; Brug, Johannes; Ausems, Marlein; Campbell, Marci; Resnicow, Ken; Zwietering, Paul J; van Breukelen, Gerard; van Mechelen, Willem; Severens, Johan L; de Vries, Hein

    2008-01-01

    Background A large proportion of adults fail to meet public health guidelines for physical activity as well as fruit, vegetable and fat intake. Interventions are needed to improve these health behaviors. Both computer tailoring and motivational interviewing have shown themselves to be promising techniques for health behavior change. The Vitalum project aims to compare the efficacy of these techniques in improving the health behaviors of adults aged 45–70. This paper describes the design of the Vitalum study. Methods/Design Dutch general medical practices (N = 23) were recruited via a registration network or by personal invitation. The participants were then enrolled through these general practices using an invitational letter. They (n = 2,881) received a written baseline questionnaire to assess health behaviors, and potential psychosocial and socio-demographic behavioral determinants. A power analysis indicated that 1,600 participants who were failing to meet the guidelines for physical activity and either fruit or vegetable consumption were needed. Eligible participants were stratified based on hypertension status and randomized into one of four intervention groups: tailored print communication, telephone motivational interviewing, combined, and control. The first two groups either received four letters or took part in four interviews, whereas the combined group received two letters and took part in two interviews in turns at 5, 13, 30 and 43 weeks after returning the baseline questionnaire. Each letter and interview focused on physical activity or nutrition behavior. The participants also took part in a telephone survey 25 weeks after baseline to gather new information for tailoring. There were two follow-up questionnaires, at 47 and 73 weeks after baseline, to measure short- and long-term effects. The control group received a tailored letter after the last posttest. The process, efficacy and cost-effectiveness of the interventions will be examined by means of

  14. MRPrimerW: a tool for rapid design of valid high-quality primers for multiple target qPCR experiments.

    PubMed

    Kim, Hyerin; Kang, NaNa; An, KyuHyeon; Koo, JaeHyung; Kim, Min-Soo

    2016-07-08

    Design of high-quality primers for multiple target sequences is essential for qPCR experiments, but is challenging due to the need to consider both homology tests on off-target sequences and the same stringent filtering constraints on the primers. Existing web servers for primer design have major drawbacks, including requiring the use of BLAST-like tools for homology tests, lack of support for ranking of primers, TaqMan probes and simultaneous design of primers against multiple targets. Due to the large-scale computational overhead, the few web servers supporting homology tests use heuristic approaches or perform homology tests within a limited scope. Here, we describe the MRPrimerW, which performs complete homology testing, supports batch design of primers for multi-target qPCR experiments, supports design of TaqMan probes and ranks the resulting primers to return the top-1 best primers to the user. To ensure high accuracy, we adopted the core algorithm of a previously reported MapReduce-based method, MRPrimer, but completely redesigned it to allow users to receive query results quickly in a web interface, without requiring a MapReduce cluster or a long computation. MRPrimerW provides primer design services and a complete set of 341 963 135 in silico validated primers covering 99% of human and mouse genes. Free access: http://MRPrimerW.com. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. MRPrimerW: a tool for rapid design of valid high-quality primers for multiple target qPCR experiments

    PubMed Central

    Kim, Hyerin; Kang, NaNa; An, KyuHyeon; Koo, JaeHyung; Kim, Min-Soo

    2016-01-01

    Design of high-quality primers for multiple target sequences is essential for qPCR experiments, but is challenging due to the need to consider both homology tests on off-target sequences and the same stringent filtering constraints on the primers. Existing web servers for primer design have major drawbacks, including requiring the use of BLAST-like tools for homology tests, lack of support for ranking of primers, TaqMan probes and simultaneous design of primers against multiple targets. Due to the large-scale computational overhead, the few web servers supporting homology tests use heuristic approaches or perform homology tests within a limited scope. Here, we describe the MRPrimerW, which performs complete homology testing, supports batch design of primers for multi-target qPCR experiments, supports design of TaqMan probes and ranks the resulting primers to return the top-1 best primers to the user. To ensure high accuracy, we adopted the core algorithm of a previously reported MapReduce-based method, MRPrimer, but completely redesigned it to allow users to receive query results quickly in a web interface, without requiring a MapReduce cluster or a long computation. MRPrimerW provides primer design services and a complete set of 341 963 135 in silico validated primers covering 99% of human and mouse genes. Free access: http://MRPrimerW.com. PMID:27154272

  16. Game Design and Learning: A Conjectural Analysis of How Massively Multiple Online Role-Playing Games (MMORPGs) Foster Intrinsic Motivation

    ERIC Educational Resources Information Center

    Dickey, Michele D.

    2007-01-01

    During the past two decades, the popularity of computer and video games has prompted games to become a source of study for educational researchers and instructional designers investigating how various aspects of game design might be appropriated, borrowed, and re-purposed for the design of educational materials. The purpose of this paper is to…

  17. Game Design and Learning: A Conjectural Analysis of How Massively Multiple Online Role-Playing Games (MMORPGs) Foster Intrinsic Motivation

    ERIC Educational Resources Information Center

    Dickey, Michele D.

    2007-01-01

    During the past two decades, the popularity of computer and video games has prompted games to become a source of study for educational researchers and instructional designers investigating how various aspects of game design might be appropriated, borrowed, and re-purposed for the design of educational materials. The purpose of this paper is to…

  18. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-dose study should be crossover in design, unless a parallel design or other design is more appropriate... scientific reasons, the drug elimination period should be either: (i) At least five times the half-life of... or urine; or (ii) At least five times the half-life of decay of the acute pharmacological effect. (c...

  19. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...-dose study should be crossover in design, unless a parallel design or other design is more appropriate... scientific reasons, the drug elimination period should be either: (i) At least five times the half-life of... or urine; or (ii) At least five times the half-life of decay of the acute pharmacological effect. (c...

  20. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-dose study should be crossover in design, unless a parallel design or other design is more appropriate... scientific reasons, the drug elimination period should be either: (i) At least five times the half-life of... or urine; or (ii) At least five times the half-life of decay of the acute pharmacological effect. (c...